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If 4x^(3)-2x^(2)+5x-8 is divided by (x-2...

If `4x^(3)-2x^(2)+5x-8` is divided by (x-2), what will be the remainder ?

A

42

B

26

C

81

D

16

Text Solution

AI Generated Solution

The correct Answer is:
To find the remainder when the polynomial \( 4x^3 - 2x^2 + 5x - 8 \) is divided by \( x - 2 \), we can use the Remainder Theorem. According to the theorem, the remainder of the division of a polynomial \( f(x) \) by \( x - c \) is equal to \( f(c) \). ### Step-by-Step Solution: 1. **Identify the polynomial and the divisor**: The polynomial is \( f(x) = 4x^3 - 2x^2 + 5x - 8 \) and the divisor is \( x - 2 \). 2. **Set the divisor equal to zero to find \( c \)**: \[ x - 2 = 0 \implies x = 2 \] 3. **Substitute \( c = 2 \) into the polynomial**: We need to calculate \( f(2) \): \[ f(2) = 4(2)^3 - 2(2)^2 + 5(2) - 8 \] 4. **Calculate each term**: - Calculate \( 4(2)^3 \): \[ 4(2^3) = 4(8) = 32 \] - Calculate \( -2(2)^2 \): \[ -2(2^2) = -2(4) = -8 \] - Calculate \( 5(2) \): \[ 5(2) = 10 \] - The constant term is \( -8 \). 5. **Combine the results**: Now, substitute these values back into the equation: \[ f(2) = 32 - 8 + 10 - 8 \] 6. **Perform the arithmetic**: - First, combine \( 32 - 8 = 24 \) - Then, \( 24 + 10 = 34 \) - Finally, \( 34 - 8 = 26 \) 7. **Conclusion**: The remainder when \( 4x^3 - 2x^2 + 5x - 8 \) is divided by \( x - 2 \) is \( 26 \). ### Final Answer: The remainder is \( 26 \).
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