Question

if tanA=cotA,prove that A+B=90°​

Answer 1

Answer:

tanA = cotA

cot(90 - A) = cot A

90 - A = A

90 = A +A

90 = 2A

A = 90 / 2 = 45

Answer 2

Answer:

tan A = cot B ........ (1)

also, tan A = cot (90-A)............(2)

...complimentary angle

From equation 1 and 2

cot B = cot (90-A)

B = 90 - A

90 = A+B

A+B = 90 ..............( proved)