Let's divide \( 9x^3 + 12x^2 + 25x + 149 \) by \( 3x + 2 \) using the long division method.
Step 1: Set up the long division.
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3x + 2 | 9x^3 + 12x^2 + 25x + 149
Step 2: Divide the leading term.
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Divide the leading term of the dividend \( 9x^3 \) by the leading term of the divisor \( 3x \). \[ \frac{9x^3}{3x} = 3x^2 \]
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Write \( 3x^2 \) above the division line.
3x^2
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3x + 2 | 9x^3 + 12x^2 + 25x + 149
Step 3: Multiply and subtract.
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Multiply \( 3x^2 \) by the entire divisor \( 3x + 2 \). \[ 3x^2 \cdot (3x + 2) = 9x^3 + 6x^2 \]
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Write this under the dividend and subtract.
3x^2
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3x + 2 | 9x^3 + 12x^2 + 25x + 149
-(9x^3 + 6x^2)
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6x^2 + 25x + 149
Step 4: Bring down and repeat.
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Bring down the next term to get \( 6x^2 + 25x \) under the line.
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Divide \( 6x^2 \) by \( 3x \). \[ \frac{6x^2}{3x} = 2x \]
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Write \( 2x \) above the division line.
3x^2 + 2x
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3x + 2 | 9x^3 + 12x^2 + 25x + 149
-(9x^3 + 6x^2)
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6x^2 + 25x + 149
-(6x^2 + 4x)
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21x + 149
Step 5: Multiply and subtract again.
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Multiply \( 2x \) by the entire divisor \( 3x + 2 \). \[ 2x \cdot (3x + 2) = 6x^2 + 4x \]
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Subtract this from the current remainder.
3x^2 + 2x
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3x + 2 | 9x^3 + 12x^2 + 25x + 149
-(9x^3 + 6x^2)
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6x^2 + 25x + 149
-(6x^2 + 4x)
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21x + 149
Step 6: Divide again.
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Divide \( 21x \) by \( 3x \). \[ \frac{21x}{3x} = 7 \]
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Write \( 7 \) above the line.
3x^2 + 2x + 7
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3x + 2 | 9x^3 + 12x^2 + 25x + 149
-(9x^3 + 6x^2)
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6x^2 + 25x + 149
-(6x^2 + 4x)
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21x + 149
-(21x + 14)
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135
Step 7: Final Remainder
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Multiply \( 7 \) by the divisor \( 3x + 2 \). \[ 7 \cdot (3x + 2) = 21x + 14 \]
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Subtract this from \( 21x + 149 \).
Resulting in 135.
Final Result
The quotient is: \[ 3x^2 + 2x + 7 \] And the remainder is: \[ 135 \]
So the answer for when dividing \( 9x^3 + 12x^2 + 25x + 149 \) by \( 3x + 2 \) is: \[ \text{Quotient: } 3x^2 + 2x + 7, \quad \text{Remainder: } 135 \]