SOLUTION: cosx + sinx tanx =secx

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Question 927318: cosx + sinx tanx =secx
Answer by srinivas.g(540) About Me  (Show Source):
You can put this solution on YOUR website!
cos+x%2Bsinx+tanx++=+cos+x+%2B+sinx++%2A+%28sin+x%2F+cos+x%29
=cos+x+%2B+%28sin+x%29%5E2+%2Fcos+x
= +cos+x+%2B+sin%5E2+%28x%29+%2F+cos+x
multiply & divide each term with cos x
=++cos+x+%2A+%28cos+x+%2Fcos+x%29+%2B%28sin%5E2+%28x%29+%2F+cos+x%29+%2A%28cos+x%2Fcos+x%29
=+cos%5E2%28x%29%2Fcos+x+%2B+sin%5E2%28x%29+%2Fcos+x
= +%28cos%5E2%28x%29%2Bsin%5E2%28x%29%29%2Fcos+x
But cos%5E2%28x%29%2Bsin%5E2%28x%29+=1
= +1%2F+cos+x
= sec x
hence proved