12. Which is the indefinite integral of y= a d. . 1/2 x x +C +C x 3 b. (2/3) x 2 +C c. e. None of these 13. The value of the definite integral for f(x)= x 3 from x=1 to x=2 is: a.15 b. 5 c. 3.75 d.7 these 14. Choose the correct value for the definite integral of y=x e x a. e-1 b. e c. e/2 d.(e-1)/2 15. When y'<0 and y\">0, y will be: a. decr & conc up b. decr & conc down d. incr & conc down 3 x 2 +C e. None of these 2 e. None of from x=0 to x=1. e. None of these c. incr & conc up