函数y=x²/x+3的导数是 函数y=sin(2x²+x)导数是

函数y=x²/x+3的导数是 函数y=sin(2x²+x)导数是
函数y=x²/x+3的导数是 函数y=sin(2x²+x)导数是

函数y=x²/x+3的导数是 函数y=sin(2x²+x)导数是
y'=[2x(x+3)-x²]/(x+3)²
=(x²+6x)/(x+3)²
y'=cos(2x²+x)·(2x²+x)'
=(4x+1)cos(2x²+x)

解
y=x²/(x+3)
y'=[(x²)'(x+3)-x²(x+3)'](x+3)²
=[2x(x+3)-x²]/(x+3)²
=(x²+6x)/(x+3)²
y=sin(2x²+4)
y'=[sin(2x²+4)]'
=cos(2x²+4)(2x²+4)'
=4xcos(2x²+4)