The value of p if px4 + 7x2 – 18 is divisible by (x – 3)A) 9/5B)

1.	The value of p if px4 + 7x2 – 18 is divisible by (x – 3)A) 9/5B) -5/9C) 5/9D) 1
Answer» Correct option is (B) -5/9 \(\because\) \(px^4+7x^2-18\) is divisible by (x - 3). \(\therefore\) When \((px^4-7x^2-18)\) is divided by (x - 3), it leaves remainder 0. \(\therefore\) \(p(3)^4+7\times3^2-18=0\) \(\Rightarrow\) 81p + 63 - 18 = 0 \(\Rightarrow\) 81p = -63 + 18 \(\Rightarrow\) 81p = -45 \(\Rightarrow\) \(p=\frac{-45}{81}=\frac{-5}{9}\) Correct option is B) -5/9

The value of p if px4 + 7x2 – 18 is divisible by (x – 3)A) 9/5B) -5/9C) 5/9D) 1

Answer»

Correct option is (B) -5/9

\(\because\) \(px^4+7x^2-18\) is divisible by (x - 3).

\(\therefore\) When \((px^4-7x^2-18)\) is divided by (x - 3), it leaves remainder 0.

\(\therefore\) \(p(3)^4+7\times3^2-18=0\)

\(\Rightarrow\) 81p + 63 - 18 = 0

\(\Rightarrow\) 81p = -63 + 18

\(\Rightarrow\) 81p = -45

\(\Rightarrow\) \(p=\frac{-45}{81}=\frac{-5}{9}\)

Correct option is B) -5/9