InterviewSolution
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निम्नलिखित को सिद्ध कीजिए । `int_(0)^((pi)/(2))tan^(3)x dx = 1-log2` |
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Answer» माना `I=int_(0)^(pi//4)2 tan^(3)x dx` `" "=2 int_(0)^(pi//4)tan^(2)x. tanx dx` `" "=2int_(0)^(pi//4)(sec^(2)x-1)tanxdx` `=2[int_(0)^(pi//4)sec^(2)x tanx dx - int_(0)^(pi//4)tanx dx]` `=2int_(0)^(pi//4)(tanx)sec^(2)x dx-2[-log|cosx|]_(0)^(pi//4)` `=2[(tan^(2)x)/(2)]_(0)^(pi//4)+2[log|cos.(pi)/(4)|-log|cos0|]` `=tan^(2)((pi)/(4))-0+2[log((1)/(sqrt2))-log1]` `=1+2log2^(-1//2)-0=1-2xx(1)/(2)log2 = 1-log2" "` यही सिद्ध करना था । |
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