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If the polynomial 6x⁴+8x³-5x²+ax+b is exactly divisible by the polynomial 2x²-5, then find the value of a and b.

User Shaun Ryan
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If the polynomial 6x^4 + 8x^3 - 5x^2 + ax + b is exactly divisible by 2x^2 - 5, then a = -20 and b = -25 to ensure a zero remainder.

If the polynomial 6x^4 + 8x^3 - 5x^2 + ax + b is exactly divisible by 2x^2 - 5, then the remainder when dividing these polynomials is zero. We can set up the division and equate the coefficients to find the values of a and b.

The long division looks like this:

```

3x^2 + 2x + 4

______________________

2x^2 - 5 | 6x^4 + 8x^3 - 5x^2 + ax + b

- (6x^4 - 15x^2)

__________________

8x^3 + 10x^2 + ax + b

- (8x^3 - 20x)

__________________

10x^2 + (a + 20)x + b

- (10x^2 - 25)

________________

(a + 20)x + b + 25

```

For the remainder to be zero, the coefficients of x and the constant term must be zero:

1. Coefficient of x: a + 20 = 0 implies a = -20

2. Constant term: b + 25 = 0 implies b = -25

Therefore, the values of (a) and (b) are a = -20 and (b = -25).

User Jaytea
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