就是重复应用复合函数的求导公式：f(g(x))'=f'(x)g'(x)
y‘=sin｛In（3+2x²）²｝'
=cos(In（3+2x²）²) *｛In（3+2x²）²｝'
=cos(In（3+2x²）²) *1/(3+2x²）²*{ (3+2x²）² }'
=cos(In（3+2x²）²) *1/(3+2x²）²* 2(3+2x²）*(3+2x²) '
=cos(In（3+2x²）²) *1/(3+2x²）²* 2(3+2x²）*4x
=cos(In（3+2x²）²) *8x/(3+2x²)