Paragraph: The sixth term of an AP is 2 and its common difference...

Paragraph: The sixth term of an AP is 2 and its common difference is greater than 1.
Question: What is the first term of the AP so that the product of the first, fourth and fifth terms is greatest?

Options

A $-4$
B $-6$
C $-8$
D $-10$

Correct answer

B. $-6$

Step-by-step solution

Since,

a=2-5 \mathrm{x}

\begin{aligned} & \Rightarrow \quad \mathrm{a}=2-5\left(\frac{8}{5}\right) \\ & \Rightarrow \quad \mathrm{a}=-6\end{aligned}

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