Q. 4 C3.8( 11 Votes )

# Prove that the following functions do not have maxima or minima:

h(x) = x^{3} + x^{2} + x +1

Answer :

h(x) = x^{3} + x^{2} + x +1

⇒ h’(x) = 3x^{2} + 2x +1

h(x) = 0

⇒ 3x^{2} + 2x +1 = 0

Therefore, there does not exist c ϵ R such that h’(c) = 0

Hence, function h does not have maxima or minima.

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