Question

Solve the equation for solutions in the interval [0, 2 π). Use algebraic methods and give exact values. Support your solution graphically. cos2x = 0

Answer 1

Explanation:

● cos 2x = 0

We khow that Pi/2 equals 0.

So

● 2x = Pi/2 or 2x= -Pi/2

Then:

● x = Pi/4 or x = -Pi/2

So the solutions are:

● x = Pi/4 + 2×k×Pi

● or x = -Pi/4 + 2×k×Pi

Where k is an integer

The picture below has a graphical solution

● Pi/4 is approximatively 0.785 and -Pi/4 is approximatively -0.785

● the output of both Pi/4 and -Pi/4 is 0

So our answer was righr

Answer 2

45° or 135°

Explanation:

Cos 2x = 0

2x = cos^-1 0

2x = 90° or 270°

x= 45° or 135°