Question

pls tell the answer fast ....
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Answer 1

Step-by-step explanation:

3 cot A =4 ; cot A=4/3 ; tan A=3/4

now check whether 1-tan^2 A / 1+tan^2 A = 1-9/16 / 1+9/16

1-tan^2 A/ 1+tan^2 A=7/25

now cos^2 A-sin^2 A=16/25-9/25=7/25

therefore 1-tan^2 A/1+tan^2 A=cos^2 A-sin^2 A

hence proved