Question 8

From Math Analysis HL Paper 1 (May 2025, TZ2)

  1. [Maximum mark: 8]

Consider the function f(x)=arccosxf(x) = \arccos x for 1x1-1 \leq x \leq 1.

(a) On the set of axes below sketch the graph of y=f(x)y = f(x).
On your sketch clearly indicate the yy-intercept and coordinates of the end points. [2]

A set of Cartesian axes with x and y labels, provided for sketching the graph of y = f(x) = arccosx.
A set of Cartesian axes with x and y labels, provided for sketching the graph of y = f(x) = arccosx.

(b) Solve arccos(x)+arccos(x3)=3π2\arccos(x) + \arccos(x\sqrt{3}) = \frac{3\pi}{2}, for 13x13-\frac{1}{\sqrt{3}} \leq x \leq \frac{1}{\sqrt{3}}. [6]