Question

if sinA = x/y , prove that (cosA+ cotA)xy = x √(y^2 - x^2) + √y(y^2-x^2)​

Answer 1

Step-by-step explanation:

sinA = x/y

use Pythagoras theorem

cosA = (√y² - x²)/y

cotA = (√y² - x²)/x

(cosA + cotA)xy                 .............(1)

put the values of cosA and cotA in equation (1)

{(√y² - x²)/y + (√y² - x²)/x}xy

(√y² - x²)x + (√y² - x²)y

hence prove