A.  n{xn-1sec2xn+tann-1xsec2x+xn-1/1+x2n}

B.  -1

C.  1

D.  none

Correct Answer :
n{xn-1sec2xn+tann-1xsec2x+xn-1/1+x2n}
Explanation :
No Explanation available for this question
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