Question

If 3 cot A = 4 find cos²A-sin²A​

Answer 1

Answer:

7/25

Step-by-step explanation:

3 cot A = 4

SO,

cot A = 4/3

cot A = base/perpendicular

by pythagoras theorem,

we can find hypotenuse which is equal to 5 here.

hypotenuse = 5

base = 4

perpendicular = 3

cos A = base/hypotenuse = 4/5

so,

cos²A = (4/5)²

=> 16/25

sin A = perpendicular/hypotenuse = 3/5

so,

sin²A = (3/5)²

=> 9/25

therefore,

cos²A - sin²A = (16/25) - (9/25)

=>7/25

Answer 2

7 / 25 is the correct answer.