421

a)
f\left(x\right)=\left(x^2+3\right)^{11}
s\left(x\right)=x^2+3
u\left(x\right)=x^{11}
b) 
f\left(x\right)=\left(x^2+3\right)^{11}
D\left(u\left(s\left(x\right)\right)\right)=u'\left(s\left(x\right)\right)s'\left(x\right)
11\cdot\left(x^2+3\right)^{10}\cdot2x=22x\left(x^2+3\right)^{10}