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问题: 大学求极限的问题

求sinx的tanx次幂的极限,其中x趋近于π/2,谢谢回答,偶不会输入一些数学符号,谢谢

解答:

lim<x→π/2>(sinx)^tanx
=lim<x→π/2>[1+(sinx-1)]^tanx
=lim<x→π/2>{[1+(sinx-1)]^[1/(sinx-1)]}^[tanx*(sinx-1)]
=e^lim<x→π/2>[tanx*(sinx-1)]
=e^lim<x→π/2>[sinx*(sinx-1)/cosx]
=e^lim<x→π/2>[(sin^2x-sinx)/cosx]
=e^lim<x→π/2>[(2sinxcosx-cosx)/(-sinx)]
=e^lim<x→π/2>[cosx(1-2sinx)/sinx]
=e^[0*(1-2)/1]
=e^0
=1