Suppose that f is continuous on [xo, x1 ] and differentiable on (x0, x1 ). Then we can find a number a E (x0, x1 ) such that Select one: of ( a ) = - f (xo) - f (x1) X1 - XO 0 f' ( a ) = f (x0) - f (x1) XO - X1 Of' ( a ) = f (x1) + f(xo) xo + X1 of'( a ) = f (xo) - f (x1 ) X1 + Xo