f(x)=2x3+ax2+bx let, a=−1,b=1 Given that f(x) satisfy Rolle's theorem in interval [-1,1] f(x) must satisfy two conditions. (1) f(a)=f(b) (2) f′(c)=0 (c should be between a and b ) f(a)=f(1)=2(1)3+a(1)2+b(1)=2+a+b f(b)=f(−1)=2(−1)3+a(−1)2+b(−1) =−2+a−b f(a)=f(b) 2+a+b=−2+a−b 2b=−4 b=−2 (given that c=