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CBSE Class 10 Answered

PLZZ HELP
Asked by sejal2208 | 09 Feb, 2010, 09:23: PM
answered-by-expert Expert Answer

sinA + sin2A = 1

So sinA = 1-sin 2A  = cos2A  .....(i)

Consider cos2A + cos4A  = cos2A +( cos2A )2 (using 1)=  sin A+ sin 2A  = 1  (given)  

Answered by | 10 Feb, 2010, 10:58: AM

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