求y = (sinx/4)^4 + (cosx/4)^4导数,
问题描述：
求y = (sinx/4)^4 + (cosx/4)^4导数,
答
y = (sinx/4)^4 + (cosx/4)^4 y'=4(sinx/4)^3+4(cosx/4))^3 y'=1/16(sinx^3+cosx^3)
y'=1/16(2sinx^2cosx-2cosx^2sinx) y'=1/8sinxcosx(sinx-cosx)
答
是sin(x/4)?y = (sin(x/4))^4 + (cos(x/4))^4y'=4*(sin(x/4))^3*(sin(x/4))'+4*(cos(x/4))^3*(cos(x/4))'=4*(sin(x/4))^3*cos(x/4)*1/4+4*(cos(x/4))^3*(-sin(x/4))*1/4=(sin(x/4))^3*cos(x/4)-(cos(x/4))^3*sin(x/4...