Advertisements
Advertisements
प्रश्न
If x – 3 is a factor of x2 + kx + 15; the value of k is ______.
विकल्प
8
3
– 5
– 8
उत्तर
If x – 3 is a factor of x2 + kx + 15; the value of k is – 8.
Explanation:
Let f(x) = x2 + kx + 15
Given x – 3 is a factor of f(x)
∴ f(3) = 0
`\implies` 32 + k × 3 + 15 = 0
`\implies` 9 + 3k + 15 = 0
`\implies` 3k + 24 = 0
`\implies` 3k = – 24
`\implies` k = – 8
संबंधित प्रश्न
If (x + 2) and (x + 3) are factors of x3 + ax + b, find the values of 'a' and `b'.
If 2x + 1 is a factor of 2x2 + ax – 3, find the value of a.
Prove by factor theorem that
(2x+1) is a factor of 4x3 + 12x2 + 7x +1
Prove by factor theorem that
(3x-2) is a factor of 18x3 - 3x2 + 6x -12
Find the value of m ·when x3 + 3x2 -m x +4 is exactly divisible by (x-2)
Show that (x – 2) is a factor of 3x2 – x – 10 Hence factorise 3x2 – x – 10.
Show that (x – 3) is a factor of x3 – 7x2 + 15x – 9. Hence factorise x3 – 7x2 + 15 x – 9
Show that (2x + 1) is a factor of 4x3 + 12x2 + 11 x + 3 .Hence factorise 4x3 + 12x2 + 11x + 3.
Check if (x + 2) and (x – 4) are the sides of a rectangle whose area is x2 – 2x – 8 by using factor theorem
Which of the following is a factor of (x – 2)2 – (x2 – 4)?
