integral dx/(sinx^4)+(sinx^2)(cosx^2)+(cosx^4)

? dx/sinx^4+sinx^2cosx^2+cosx^4

multiplying by (sinx^2-cosx^2)in num. and denom. Both, we get

?[(sinx^2-cosx^2)/sinx^4+sinx^2cosx^2+cosx^4]dx

ð ?[(sinx^2-cosx^2)/(sinx^2-cosx^2)^3]dx

ð ?[cos2x/(cos2x)^3]dx

ð ?[1/(cos2x)^2]dx

ð ?[(sec2x)^2]dx

ð (tan2x)/2

ð ½(tan2x) Ans.

Thnaks & Regards

Rinkoo Gupta

AskIITians Faculty.