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1-tan Acot A4,check whether+tanA -sin' A or not |
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Answer» (1-tan²A)/(1 + tan²A)=2cos²A -1as sin^2a-cos^2a=2cos^2a-1=cos2a3cotA = 4 cotA = 4/3 tanA = 1/cotA = 3/4 LHS = (1-tan²A)/(1+ tan²A) = (1 - 9/16)/(1+ 9/16)= 7/25 RHS =2cos²A -1∵tanA = 3/4 ∴cosA = 4/5 = 2(4/5)² -1 = 32/25 -1 =7/25 LHS = RHS so, (1-tan²A)/(1 + tan²A)=2cos²A-1 |
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