Practicing Success
$\frac{cosA}{1-tanA}+\frac{sinA}{1-cotA}$=________. |
tan A - cot A tan A + cot A sin A cos A sin A + cos A |
sin A + cos A |
\(\frac{cosA}{1 - tanA }\) + \(\frac{sinA }{1 - cotA }\) = \(\frac{cosA}{1 - sinA / cosA}\) + \(\frac{sinA }{1 - cosA/ sinA }\) = \(\frac{cos2A}{cosA - sinA }\) + \(\frac{sin2A }{sinA - cosA }\) = \(\frac{cos2A - sin2A }{cosA - sinA }\) = cosA + sinA So , option 4 is correct answer |