Question

Complete the solution to y = cos-1(1).
a) y = 2 pi k
b) y= pi k
c) y = pi ± pi k

Answer 1

a) y = 2 pi k

Explanation:

Given the solution to the equation y to be cos⁻¹(1)

y = cos⁻¹(1)

y =0°

In trigonometry identity, the general solution for cosine function is expressed as θ = 2kπ ± n, where n is any integer.

Substituting the solution gotten to the equation above into the general formula θ = 2kπ ± n, will give;

y = 2kπ ± n

since we have just one solution, we will find the value of y at n = 0

y = 2kπ ± 0

y = 2kπ