Question

If tanA = CotB

Prove that A+B=90°

Answer 1

Answer:

Tan A=cot B

Cot (90-A)=cot B

90-A=B

90=A+B

Answer 2

tanA = cotB

_________ [ GIVEN ]

• We have to prove that A + B = 90°

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→ tanA = cotB

We know that

tan90° - Ø = cotØ

Similarly,

tan90° - B = cotB

So,

→ tanA = tan(90° - B)

tan throughout cancel.

Now.. what left is.. A = 90° - B

→ A = 90° - B

Take B to LHS

→ A + B = 90°

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A + B = 90°

____ [ HENCE PROVED ]

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