Question

Simplify cos^2 A/1+sin A

Answer 1

Answer:

$\displaystyle \frac{\cos^2(A)}{1+\sin(A)}=1-\sin(A)$

Step-by-step explanation:

We want to simplify:

$\displaystyle \frac{\cos^2(A)}{1+\sin(A)}$

Recall the Pythagorean Identity:

$\sin^2(A)+\cos^2(A)=1$

So:

$\cos^2(A)=1-\sin^2(A)$

Substitute:

$\displaystyle =\frac{1-\sin^2(A)}{1+\sin(A)}$

Factor. We can use the difference of two squares pattern:

$\displaystyle =\frac{\left(1-\sin(A))(1+\sin(A))}{1+\sin(A)}$

Cancel. Hence:

$\displaystyle \frac{\cos^2(A)}{1+\sin(A)}=1-\sin(A)$