Question 143

The value of $$[\frac{cos^2A(sinA + cosA)}{cosec^2A(sinA-cosA)} + \frac{sin^2A(sinA - cos A)}{sec^2A(sinA + cos A)}]$$$$(sec^2A - cosec^2 A)$$

Solution

Expression : $$[\frac{cos^2A(sinA + cosA)}{cosec^2A(sinA-cosA)} + \frac{sin^2A(sinA - cos A)}{sec^2A(sinA + cos A)}]$$$$(sec^2A - cosec^2 A)$$

= $$[cos^2A sin^2A \frac{(sinA + cosA)}{(sinA - cosA)} + cos^2A sin^2A \frac{(sinA - cosA)}{(sinA + cosA)}] (sec^2A - cosec^2A)$$

= $$(cos^2A sin^2A) [\frac{(sinA + cosA)^2 + (sinA - cosA)^2}{(sinA - cosA)(sinA + cosA)}] (\frac{1}{cos^2A} - \frac{1}{sin^2A})$$

= $$(cos^2A sin^2A) (\frac{sin^2A - cos^2A}{cos^2A sin^2A}) [\frac{(sin^2A + cos^2A + 2 sinA cosA) + (sin^2A + cos^2A - 2 sinA cosA)}{sin^2A - cos^2A}]$$

= $$1 + 2 sinA cosA + 1 - 2 sinA cosA$$

= $$2$$


Create a FREE account and get:

  • Free SSC Study Material - 18000 Questions
  • 230+ SSC previous papers with solutions PDF
  • 100+ SSC Online Tests for Free

cracku

Boost your Prep!

Download App