(10pts) Use the definition of the definite integral i.e., int_a^b f(x)dx=lim_(n->infty )sum_(i=1)^n f(x_(i))*Delta x, where Delta x=(b-a)/(n) and x_(i)=a+i*Delta x, to evaluate the integral int_(-1)^3 (4+3x)dx.
and xi = a + i - x, to evaluate the integral J-,(4 +3x) dx.