求下列函数的导数 y=sinx+xcosx y=2^x+log2x y=sinxcosx

1.y=sinx+xcosx
2.y=2^x+log2x
3.y=sinxcosx

---

y=sinx+xcosx
y'桐唯正=cosx+cosx+x*(-sinx)
=2cosx-xsinx
y=2^x+log2x
y'局悔=2^xln2+1/(xln2)
y=sinxcosx

y'山团=cosx*cosx+sinx*(-sinx)
=cos²x-sin²x
=cos2x

---

1.y'肆信=2cosx-xsinx
2.y'=2xln2+x分之2
3.y'=cosx的睁雹轮平方-sinx的悉信平方

---