Question

If 3 cot A=4 find Cos²A-sin²A​

Answer 1

Step-by-step explanation:

3 cot A=4

cotA=4/3=adj/opp

hyp^2=opp^2+adj^2 Pythagoras theorem

=3^2+4^2

=9+16

=25

hyp=5

cosA=adj/hyp=4/5

sinA=opp/hyp=3/5

Cos²A-sin²A =(4/5)^2 - (3/5)^2

=(16-9)/25

=7/25

Answer 2

7 / 25 is the correct answer.