Mathematics Marking Guideline Analysis - NSC Grade 10 Functions

Analysis of Exponential and Parabolic Functions (Question 3)

  • Determining the Exponential Function g(x)g(x)     * The function is defined by the general form: g(x)=bxg(x) = b^{x}.     * To solve for the base bb, a point from the graph is substituted into the equation. Using the coordinates (2;4)(2; 4), the equation becomes: 4=b24 = b^{2}.     * Solving for the base: b=2b = 2.     * Marking Criteria for 3.1 (Exponential):         * One mark for the correct substitution of the point into the equation.         * One mark for identifying the correct final value of b=2b = 2.

  • Determining the Parabolic Function h(x)h(x)     * The function is defined by the general form: h(x)=ax2+qh(x) = ax^{2} + q.     * The parameter qq represents the vertical shift or the y-intercept of the parabola. From the transcript, it is determined that: q=2q = -2.     * To solve for the coefficient aa, the point P(1;0)P(1; 0) is substituted into the equation: 0=a(1)220 = a(1)^{2} - 2.     * Solving for aa: a=2a = 2.     * Marking Criteria for 3.1 (Parabolic):         * One mark for identifying the value of q=2q = -2.         * One mark for the correct substitution of point PP.         * One mark for identifying the correct final value of a=2a = 2.

  • Coordinates of Point B     * The x-intercept of the parabolic function opposite to point PP is identified as: B(1;0)B(-1; 0).     * Marking Criteria for 3.2:         * One mark for the correct coordinates of point BB.

Determination of Linear Equations and Range

  • Calculating the Gradient and Equation of a Line (Question 3.3)     * The gradient (mm) of the line is calculated using the formula for slope: m=4021m = \frac{4 - 0}{2 - 1}.     * Calculation: m=41=4m = \frac{4}{1} = 4.     * The general linear equation is: y=mx+cy = mx + c.     * Substituting the gradient (m=4m = 4) and the point (1;0)(1; 0) to find the y-intercept (cc):         * 0=4(1)+c0 = 4(1) + c         * c=4c = -4     * The final equation of the line is: y=4x4y = 4x - 4.     * Marking Criteria for 3.3:         * One mark for the correct calculation of the gradient m=4m = 4.         * One mark for the correct value of the y-intercept cc.         * One mark for providing the final linear equation.

  • Defining the Range (Question 3.4)     * The range of the function is expressed as the set of all possible y-values.     * The range is given as: y2y \le 2.     * Alternative interval notation: y(;2]y \in (-\infty; 2].     * Marking Criteria for 3.4:         * One mark for the correct identification of the range limit and inequality/interval.

Hyperbolic Functions and Algebraic Solutions (Question 4)

  • Sketching and Properties of Hyperbolic Functions (Question 4.1.1)     * The marking guidelines specify five key components for the visual representation or analysis of the graph:         * Shape: The general curvature of the hyperbola must be correct relative to its quadrants.         * Asymptotes: Correct placement of vertical and horizontal lines that the graph approaches but never touches.         * X-intercepts: Identification of where the graph crosses the horizontal axis.         * Y-intercept: Identification of where the graph crosses the vertical axis.     * Numerical values associated with this section include: 1.51.5, 4.5-4.5, 33, 0.50.5, and 2.52.5.     * Marking Criteria for 4.1.1:         * One mark for the correct shape.         * One mark for the correct asymptotes.         * Two marks for the correct x-intercepts.         * One mark for the correct y-intercept.

  • Solving for X in a Rational Equation (Question 4.1.2)     * Equation provided: 2=1x1-2 = -\frac{1}{x} - 1.     * Step-by-step algebraic solution:         * Add 1 to both sides: 1=1x-1 = -\frac{1}{x}.         * Multiply both sides by x-x: x=1-x = 1.         * Final result: x=1x = -1.     * Marking Criteria for 4.1.2:         * One mark for the correct final answer of x=1x = -1.

Parameter Identification in Rational Functions

  • Finding the Constant K (Question 4.2.1)     * Based on the provided ratio or substitution: k2=1\frac{k}{2} = 1.     * Solving for the variable: k=2k = 2.     * Marking Criteria for 4.2.1:         * One mark for the correct identification of k=2k = 2.