Using MATLAs Symbolic Math toolbox.

Part $1$

b$.)u^{\text{'}}(t)=2u(t)+4,u(0)=0$

f$.)u^{\text{'}}(t)=-(t)+e^t,u(0)=2$

h$.)u^{\text{'}}(t)=u\frac{t}{t}+2,u(1)=3$