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Absolutely — I’d make these Calc 1 exam-style flashcards, meaning they focus not only on definitions/formulas, but also on when to use a rule, what to look for, and common traps.

📚 Calc 1 Flashcards

1. Average & Instantaneous Velocity

Flashcard 1
Q: What is average velocity?
A: Average velocity is the change in position divided by the change in time:

v_{\text{avg}}=\frac{f(b)-f(a)}{b-a}

It represents the slope of the secant line between two points.


Flashcard 2
Q: What is instantaneous velocity?
A: Instantaneous velocity is the velocity at one specific instant. It is the derivative of position:

v(t)=s'(t)

It represents the slope of the tangent line at a point.


Flashcard 3
Q: What is the difference between average and instantaneous velocity?
A:

  • Average velocity: over an interval → secant line

  • Instantaneous velocity: at one moment → tangent line


Flashcard 4
Q: How can instantaneous velocity be found using a limit?

v(a)=\lim_{h\to0}\frac{f(a+h)-f(a)}{h}

This is the definition of the derivative.


2. Inverse Trig Functions

Flashcard 5
Q: What does \sin^{-1}(x) mean?
A: It means inverse sine (arcsin), not 1/\sin(x).

\sin^{-1}(x)=\arcsin(x)

It answers: “What angle has sine equal to x?”


Flashcard 6
Q: What does \cos^{-1}(x) mean?
A: Inverse cosine:

\cos^{-1}(x)=\arccos(x)

It asks: “What angle has cosine equal to x?”


Flashcard 7
Q: What does \tan^{-1}(x) mean?
A: Inverse tangent:

\tan^{-1}(x)=\arctan(x)

It asks: “What angle has tangent equal to x?”


Flashcard 8
Q: What are the domains of inverse trig functions?

A:

\arcsin(x): [-1,1]

\arccos(x): [-1,1]

\arctan(x): (-\infty,\infty)


3. Basic Trig Functions

Flashcard 9
Q: What are SOH-CAH-TOA?

A:

SOH

\sin(\theta)=\frac{\text{opposite}}{\text{hypotenuse}}

CAH

\cos(\theta)=\frac{\text{adjacent}}{\text{hypotenuse}}

TOA

\tan(\theta)=\frac{\text{opposite}}{\text{adjacent}}


Flashcard 10
Q: What is the relationship between tangent, sine, and cosine?

A:

\tan(x)=\frac{\sin(x)}{\cos(x)}

Therefore, tangent is undefined whenever:

\cos(x)=0


Flashcard 11
Q: What are the reciprocal trig functions?

A:

\csc x=\frac1{\sin x}

\sec x=\frac1{\cos x}

\cot x=\frac1{\tan x}


4. Unit Circle & Trig Signs

Flashcard 12
Q: In which quadrants is sine positive?

A: Quadrants I and II.


Flashcard 13
Q: In which quadrants is cosine positive?

A: Quadrants I and IV.


Flashcard 14
Q: In which quadrants is tangent positive?

A: Quadrants I and III.


Flashcard 15
Q: What is the ASTC rule?

A: Moving counterclockwise:

  • I: All positive

  • II: Sine positive

  • III: Tangent positive

  • IV: Cosine positive

A common mnemonic is All Students Take Calculus.


5. Important Trig Identities

Flashcard 16
Q: What is the Pythagorean trig identity?

A:

\boxed{\sin^2x+\cos^2x=1}


Flashcard 17
Q: What identities can be obtained from \sin^2x+\cos^2x=1?

A:

Divide by \cos^2x:

\tan^2x+1=\sec^2x

Divide by \sin^2x:

1+\cot^2x=\csc^2x


Flashcard 18
Q: What are the reciprocal identities?

A:

\sin x=\frac1{\csc x}

\cos x=\frac1{\sec x}

\tan x=\frac1{\cot x}


Flashcard 19
Q: What is the quotient identity for tangent?

A:

\boxed{\tan x=\frac{\sin x}{\cos x}}


6. Limits at Infinity

Flashcard 20
Q: What happens when the denominator has a higher degree than the numerator as x\to\infty?

A: The limit is:

\boxed{0}

Example:

\lim_{x\to\infty}\frac{x^2+1}{x^3+4}=0

Bigger power on bottom → 0.


Flashcard 21
Q: What happens when the numerator and denominator have the same degree?

A: The limit is the ratio of the leading coefficients.

Example:

\lim_{x\to\infty}\frac{3x^2+1}{5x^2-2}
=\frac35


Flashcard 22
Q: What happens when the numerator has a higher degree than the denominator?

A: The function generally approaches:

\boxed{\pm\infty}

or may have no finite horizontal asymptote.

The exact behavior depends on the leading terms and direction of infinity.


Flashcard 23
Q: What is the degree rule for rational functions at infinity?

A:

Degrees

Limit behavior

Top < Bottom

0

Top = Bottom

Ratio of leading coefficients

Top > Bottom

Usually \pm\infty or polynomial-type growth


7. Limits Involving Sin, Cos & Tan

Flashcard 24
Q: What are the basic limits of sine and cosine as x\to\infty?

A:

\lim_{x\to\infty}\sin x

and

\lim_{x\to\infty}\cos x

do not exist because they continually oscillate.


Flashcard 25
Q: Is \lim_{x\to\infty}\tan x finite?

A: No.

\lim_{x\to\infty}\tan x

does not exist because tangent repeatedly becomes undefined and oscillates.


Flashcard 26
Q: What is an important trig limit in Calc 1?

A:

\boxed{\lim_{x\to0}\frac{\sin x}{x}=1}

IMPORTANT: This requires x to be measured in radians.


Flashcard 27
Q: What is another important trig limit?

A:

\boxed{\lim_{x\to0}\frac{\tan x}{x}=1}

Again, angles must be in radians.


Flashcard 28
Q: What happens when evaluating a limit like

\lim_{x\to a}\sin x

?

A: Substitute a:

\sin(a)

Sine and cosine are continuous everywhere.


Flashcard 29
Q: What happens when evaluating

\lim_{x\to a}\cos x

?

A: Direct substitution works:

\lim_{x\to a}\cos x=\cos(a)


Flashcard 30
Q: When can you directly evaluate a limit involving \tan x?

A: When \tan(a) is defined.

Since:

\tan x=\frac{\sin x}{\cos x}

tangent is undefined when:

\cos(a)=0


8. Limit Laws

Flashcard 31
Q: What is the constant limit law?

A:

\lim_{x\to a}c=c


Flashcard 32
Q: What is the sum law?

A:

\lim[f(x)+g(x)]
=
\lim f(x)+\lim g(x)


Flashcard 33
Q: What is the difference law?

A:

\lim[f(x)-g(x)]
=
\lim f(x)-\lim g(x)


Flashcard 34
Q: What is the product law?

A:

\lim[f(x)g(x)]
=
(\lim f(x))(\lim g(x))


Flashcard 35
Q: What is the quotient law?

A:

\lim\frac{f(x)}{g(x)}
=
\frac{\lim f(x)}{\lim g(x)}

provided:

\lim g(x)\neq0


Flashcard 36
Q: What is the power law?

A:

\lim[f(x)]^n
=
[\lim f(x)]^n


9. Absolute Value & Limits

Flashcard 37
Q: What does absolute value mean?

A: Absolute value represents distance from zero, so it is always nonnegative:

|x|\ge0


Flashcard 38
Q: What is

|x|

as a piecewise function?

A:

|x|=
\begin{cases}
x,&x\ge0\\
-x,&x<0
\end{cases}


Flashcard 39
Q: How do you evaluate

\lim_{x\to a}|f(x)|

if \lim_{x\to a}f(x)=L?

A:

\boxed{\lim_{x\to a}|f(x)|=|L|}

because absolute value is continuous.


Flashcard 40
Q: What should you remember when an absolute value contains x-a?

A: Check whether the expression changes sign around a.

For example:

|x-a|

behaves differently depending on whether:

x<a

or

x>a


10. Piecewise Functions

Flashcard 41
Q: What is a piecewise function?

A: A function defined using different formulas over different intervals.

Example:

f(x)=
\begin{cases}
x+1,&x<2\\
x^2,&x\ge2
\end{cases}


Flashcard 42
Q: How do you evaluate a piecewise function?

A: Determine which condition contains your x-value, then use only that formula.


Flashcard 43
Q: What is the biggest mistake when evaluating piecewise functions?

A: Using the wrong piece.

Always check the inequality first:

x<2,\quad x\le2,\quad x>2,\quad x\ge2


Flashcard 44
Q: How do you evaluate a limit at the boundary of a piecewise function?

A: Calculate the:

Left-hand limit

\lim_{x\to a^-}f(x)

and the:

Right-hand limit

\lim_{x\to a^+}f(x)

Then compare them.


Flashcard 45
Q: When does a two-sided limit exist?

A:

\boxed{
\lim_{x\to a}f(x)\text{ exists}
}

only if:

\boxed{
\lim_{x\to a^-}f(x)
=
\lim_{x\to a^+}f(x)
}


Flashcard 46
Q: Does f(a) have to equal the limit for the limit to exist?

A: No.

The function’s actual value at a can be different from the limit—or even undefined.


11. L’Hôpital’s Rule

Flashcard 47
Q: When can you use L’Hôpital’s Rule?

A: When direct substitution produces one of these indeterminate forms:

\boxed{\frac00}

or

\boxed{\frac{\pm\infty}{\pm\infty}}


Flashcard 48
Q: What does L’Hôpital’s Rule say?

A:

If the limit produces 0/0 or \infty/\infty:

\boxed{
\lim_{x\to a}\frac{f(x)}{g(x)}
=
\lim_{x\to a}\frac{f'(x)}{g'(x)}
}

when the conditions for the rule are satisfied.


Flashcard 49
Q: What is the first step before using L’Hôpital’s Rule?

A: Try direct substitution first.

Don’t automatically differentiate.


Flashcard 50
Q: What should you do if L’Hôpital’s Rule still gives 0/0?

A: You can generally apply L’Hôpital’s Rule again, if the resulting limit still satisfies the conditions.


Flashcard 51
Q: Can you use L’Hôpital’s Rule on 0\cdot\infty?

A: Not directly.

Rewrite it as a quotient first.

For example:

f(x)g(x)
=
\frac{f(x)}{1/g(x)}

Then check whether it becomes 0/0 or \infty/\infty.


Flashcard 52
Q: Can L’Hôpital’s Rule be used directly on \infty-\infty?

A: No.

Rewrite the expression into a quotient first.


12. Conjugates

Flashcard 53
Q: When should you consider using a conjugate?

A: When a limit contains radicals and direct substitution produces:

\boxed{0/0}

A conjugate can eliminate the radical difference.


Flashcard 54
Q: What is the conjugate of

\sqrt{x}+3

?

A:

\sqrt{x}-3


Flashcard 55
Q: What identity makes conjugates useful?

A:

(a+b)(a-b)=a^2-b^2

For radicals:

(\sqrt{x}-a)(\sqrt{x}+a)=x-a^2


Flashcard 56
Q: What are the basic steps for solving a radical limit with a conjugate?

A:

  1. Substitute.

  2. If you get 0/0, identify the radical expression.

  3. Multiply by the conjugate.

  4. Simplify.

  5. Cancel the common factor.

  6. Substitute again.


13. Vertical Asymptotes

Flashcard 57
Q: What is a vertical asymptote?

A: A vertical line:

\boxed{x=a}

where the function approaches +\infty, -\infty, or otherwise becomes unbounded as x approaches a.


Flashcard 58
Q: How do you find vertical asymptotes of a rational function?

A: Usually:

  1. Factor numerator and denominator.

  2. Cancel common factors only if appropriate.

  3. Set the remaining denominator equal to zero.

Example:

f(x)=\frac{1}{x-3}

Vertical asymptote:

\boxed{x=3}


Flashcard 59
Q: What is the difference between a hole and a vertical asymptote?

A: If a factor cancels, it usually creates a hole.

If the denominator remains zero after simplifying, it can create a vertical asymptote.


14. Horizontal Asymptotes

Flashcard 60
Q: What is a horizontal asymptote?

A: A horizontal line:

\boxed{y=L}

that the function approaches as:

x\to\infty

or

x\to-\infty


Flashcard 61
Q: How do you find a horizontal asymptote of a rational function?

A: Compare the degrees of the numerator and denominator.


Flashcard 62
Q: If numerator degree < denominator degree, what is the horizontal asymptote?

A:

\boxed{y=0}


Flashcard 63
Q: If numerator degree = denominator degree, what is the horizontal asymptote?

A: The ratio of the leading coefficients.

Example:

\frac{4x^2+1}{2x^2-5}

has:

\boxed{y=2}


Flashcard 64
Q: If numerator degree > denominator degree, is there a horizontal asymptote?

A: Generally no.

There may instead be a slant/oblique or polynomial asymptote depending on the function.


15. BIG Calc 1 Trig Cheat-Sheet Flashcards

Flashcard 65
Q: What are the six basic trig functions?

A:

\sin x,\quad \cos x,\quad \tan x

\csc x,\quad \sec x,\quad \cot x


Flashcard 66
Q: When is sine equal to zero?

A:

\sin x=0

at:

x=n\pi

where n is any integer.


Flashcard 67
Q: When is cosine equal to zero?

A:

\cos x=0

at:

x=\frac{\pi}{2}+n\pi


Flashcard 68
Q: When is tangent undefined?

A:

\tan x=\frac{\sin x}{\cos x}

so tangent is undefined when:

\boxed{\cos x=0}

Therefore:

x=\frac{\pi}{2}+n\pi


Flashcard 69
Q: What are the ranges of sine and cosine?

A:

\boxed{-1\le\sin x\le1}

\boxed{-1\le\cos x\le1}


Flashcard 70
Q: Is tangent bounded between -1 and 1?

A: No.

Tangent can have any real value:

\boxed{-\infty<\tan x<\infty}

where it is defined.


Flashcard 71
Q: What is the period of sine and cosine?

A:

\boxed{2\pi}


Flashcard 72
Q: What is the period of tangent?

A:

\boxed{\pi}


Flashcard 73
Q: What is the amplitude of y=A\sin x or y=A\cos x?

A:

\boxed{|A|}


Flashcard 74
Q: What is the general form of a sine/cosine function?

A:

y=A\sin(Bx-C)+D

or

y=A\cos(Bx-C)+D

where:

  • |A| = amplitude

  • 2\pi/|B| = period

  • C/B = phase shift

  • D = vertical shift


Flashcard 75
Q: What is the general form of tangent?

A:

y=A\tan(Bx-C)+D

Its period is:

\boxed{\frac{\pi}{|B|}}


⭐ Most Important “What Do I Do?” Flashcard

Flashcard 76
Q: When I see a limit problem, what should I do FIRST?

A:

Step 1 — Substitute.

Ask:

What happens when I plug in the number?

If you get a normal number:

DONE.

If you get 0/0:

Try:

  • factoring

  • simplifying

  • conjugate

  • trig identities

  • L’Hôpital’s Rule

If you get \frac{\infty}{\infty}:

Consider:

  • dividing by the highest power

  • L’Hôpital’s Rule

If you get \infty-\infty:

Rewrite/simplify first.

If you get 0\cdot\infty:

Rewrite as a quotient first.


🧠 One More “Infinity” Flashcard

Flashcard 77
Q: What are the most important infinity rules for rational functions?

A:

Think “compare powers.”

\boxed{\text{Bottom bigger → }0}

\boxed{\text{Same power → leading coefficient ratio}}

\boxed{\text{Top bigger → no finite horizontal asymptote}}

And remember:

\boxed{\infty\text{ is NOT a number}}

So you cannot treat infinity like an ordinary number and perform normal arithmetic with it.


🔥 What I would memorize first for your Calc 1 quiz

If your quiz is coming up soon, prioritize these in this order:

  1. Limit laws

  2. Direct substitution

  3. 0/0 → factor/conjugate/L’Hôpital

  4. Limits at infinity

  5. Piecewise left/right limits

  6. Basic trig functions + unit circle

  7. \sin^2x+\cos^2x=1

  8. \tan x=\sin x/\cos x

  9. \lim_{x\to0}\sin x/x=1

  10. Vertical vs. horizontal asymptotes

  11. Average vs. instantaneous velocity

  12. Inverse trig functions

The biggest thing for your quiz is not just memorizing formulas. You want to be able to see a problem and immediately think “What type of problem is this, and which method should I use?”