If p(x) = x3 + x2 + ax + 115 is exactly divisible by (x + 5) then a = ?
Given, p(x) = x3 + x2 + ax + 115
(x3 + x2 + ax + 115) is exactly divisible by (x + 5)
Hence, substituting x = -5 will give us the value of a
⇒ (-5)3 + (-5)2 + a (-5) + 115 = 0
⇒ -125 + 25 – 5a + 115 = 0
⇒ 5a = 15
⸫ a = 3