åå¼ = lim(x->0) [1+(sinx)^2-cosx]/{(tanx)^2 *[æ ¹å·(1+(sinx)^2)+æ ¹å·cosx]}
= (1/2)*lim(x->0) [1+(sinx)^2-cosx]/(tanx)^2
= (1/2)*lim(x->0) (2sinxcosx+sinx)/[2tanx/(cosx)^2]
= (1/4)*lim(x->0) sinx/(2tanx) *lim(x->0) (2cosx+1)*(cosx)^2
= (1/4)*(1/2)*3
= 3/8
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