Question

Find the value of 9sin^2 A - 9 + 9cos^2 A​

Answer 1

Answer:

the value is 0

$9 \sin {}^{2} a - 9 + 9 \cos^{2} a$

$sin {}^{2} a = 1 + cos {}^{2} a$

instert this formula

$9(1 + \cos {}^{2}a ) - 9(1 + cos {}^{2} a)$

$9 - 9$

0