How do you write an algebraic expression that is equivalent to cos(arcsin(xhr))?

2 Answers
Dec 30, 2016

cos(arcsin(xhr))=1(xhr)2

Explanation:

By definition:

y=arcsin(xhr)

is a number such that:

siny=xhr

Then we have that:

1sin2y=cosy

and thus:

cos(arcsin(xhr))=1(xhr)2

Dec 30, 2016

Use the identity cos(θ)=±1sin2(θ) and then simplify.

Explanation:

We substitute sin1(xhr) for θ:

cos(sin1(xhr))=±1sin2(sin1(xhr))

A property of a function and its inverse, f(f1(x))=x, makes the sine and the inverse sine disappear:

cos(sin1(xhr))=±1(xhr)2

Make a common denominator:

cos(sin1(xhr))=±r2r2(xh)2r2

cos(sin1(xhr))=±r2(xh)2r2

cos(sin1(xhr))=±r2(xh)2r