Math

A number is not prime its called composite any composite number can be written as a product (multiplication) Or prime numbers

$42=2\cdot3\cdot7$

Find the prime factorization

180

18×10

A fraction is a rational number written in the form

$\frac{a}{b}$ $=\frac{a}{b}=b\sqrt{a}$

Fractions are not unique numbers

$\frac12=\frac48$ $\frac{50}{100}=\frac{5}{10}\cdot\frac{10}{10}=\frac{5}{10}=\frac{5}{2\cdot5}=\frac12$

$\frac{108}{72}=\frac{\left(9\cdot12\right)}{9\cdot8}=\frac{12}{8}=\frac{\left(4\cdot3\right)}{4\cdot2}=\frac32$

Comment on division with zero

Zero with numerator zero with denominator

$\frac{0}{n}=0$ $\frac{n}{0}=$ undefined

N = some answer not zero

All real numbers can be written a number line

← numbers to the left get smaller

Symbols

Equality relationships and order relationships

= equals to $<$ less than equal

$\neq$ $\neq$not equals to</p><p class="has-focus">.$\thickapprox$approximately equal to</p><p class="has-focus">$x$less than of equal to 2</p><p class="has-focus">Interval notation:</p><p class="has-focus">.,$\left(-\infty,2\right)$$ ]

Infinity is always starting with parentheses