Question

Let angle d be an acute angle such that cos d= 0.64. Use a calculator to approximate the measure of angle d to the nearest tenth of a degree

Answer 1

ANSWER

$d=50.2^o$

EXPLANATION

We are given that d is an acute angle, such that:

$\cos (d)=0.64$

To find the value of d, we have to find the cosine inverse of both sides of the function.

That is:

$\cos ^{-1}(\cos (d))=\cos ^{-1}(0.64)$

Now, simplify:

$\begin{gathered} d=cos^{-1}(0.64) \\ d=50.2^o \end{gathered}$

That is the value of d.