Question

cot (tan-'a + cot-'a)
answer this question​

Answer 1

Cot (tan-'a + cot-'a)

=》Cot $\frac {}{2}$

=》Cot $\frac {180°}{2}$

=》Cot = $90°$

=》0

Answer 2

$\rule{200}3$

$\Huge{\purple{\underline{\textsf{Question}}}}$

$\pink\longrightarrow$ $\pink{\sf cot ( tan^{-1}a + cot^{-1}a )}$

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$\Huge{\orange{\underline{\textsf{Answer}}}}$

$\green\longrightarrow$ $\green{\sf cot ( tan^{-1}a + cot^{-1}a )}$

$\green\longrightarrow$ $\green{\sf cot = (\frac{\pi}{2})}$ $\red{\rm (As \: tan^{-1}x + cot^{-1}x = \frac{\pi}{2})}$

$\green\longrightarrow$ $\green{\sf cot = (\frac{180^{\circ}}{2})}$

$\green\longrightarrow$ $\green{\sf cot (90^{\circ})}$ $\red{\rm (As \: cot 90^{\circ} = 0)}$

$\green\longrightarrow$ $\boxed{\green{\sf 0}}$ $\orange\star$

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