Question : The displacement of a particle undergoing rectilinear motion along the 𝑥-axis is given by 𝑥 = (2𝑡2 + 21𝑡 2 + 60𝑡 + 6). The acceleration of the particle when its velocity is zero is
(A) 36ms^{-2}
(B) 9ms^{-2}
(C) -9ms^{-2}
(D) -18ms^{-2}
Answer : option (D)
Solution :
