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Using the factor theorem, show that (x-2...

Using the factor theorem, show that (x-2) is a factor of `3x^(2)-5x-2`. Hence factorise the given expression.

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To show that \( (x-2) \) is a factor of \( 3x^2 - 5x - 2 \) using the Factor Theorem, we will follow these steps: ### Step 1: Define the polynomial Let \( p(x) = 3x^2 - 5x - 2 \). ### Step 2: Apply the Factor Theorem According to the Factor Theorem, \( (x - c) \) is a factor of \( p(x) \) if \( p(c) = 0 \). Here, we will check if \( (x - 2) \) is a factor by substituting \( x = 2 \) into \( p(x) \). ### Step 3: Substitute \( x = 2 \) into \( p(x) \) Calculate \( p(2) \): \[ p(2) = 3(2)^2 - 5(2) - 2 \] \[ = 3(4) - 10 - 2 \] \[ = 12 - 10 - 2 \] \[ = 12 - 12 \] \[ = 0 \] ### Step 4: Conclusion from the Factor Theorem Since \( p(2) = 0 \), we conclude that \( (x - 2) \) is indeed a factor of \( 3x^2 - 5x - 2 \). ### Step 5: Factor the polynomial Now, we will factor \( 3x^2 - 5x - 2 \) using polynomial long division by dividing \( p(x) \) by \( (x - 2) \). 1. Divide the leading term: \( 3x^2 \div x = 3x \). 2. Multiply \( 3x \) by \( (x - 2) \): \[ 3x(x - 2) = 3x^2 - 6x \] 3. Subtract this from \( p(x) \): \[ (3x^2 - 5x - 2) - (3x^2 - 6x) = (-5x + 6x) - 2 = x - 2 \] 4. Now, divide \( x - 2 \) by \( (x - 2) \): \[ (x - 2) \div (x - 2) = 1 \] 5. Therefore, the complete factorization is: \[ 3x^2 - 5x - 2 = (x - 2)(3x + 1) \] ### Final Answer Thus, the factorization of \( 3x^2 - 5x - 2 \) is: \[ 3x^2 - 5x - 2 = (x - 2)(3x + 1) \] ---
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ICSE-REMAINDER AND FACTOR THEOREMS-Exercise 8C
  1. Using the factor theorem, show that (x-2) is a factor of 3x^(2)-5x-2. ...

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  2. Show that (x - 1) is a factor of x^(3)-7x^(2)+14x-8 Hence, completel...

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  3. Using Remainder Theorem, factorise : x^(3)+10x^2-37x+26 completely.

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  4. When x^(3)+3x^(2)-mx+4 is divided by x -2, the remainder is m + 3. Fin...

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  5. What should be subtracted from 3x^(3)-8x^(2)+4x - 3, so that the resul...

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  6. If (x + 1) and (x - 2) are factors of x^(3)+ (a + 1)x^2 -(b - 2) x-6, ...

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  7. If x= 2 is a factor of x^2+ ax + b and a +b =1. find the values of a a...

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  8. Factorise x^(3)+6x^(2)+11x+6 completely using factor theorem.

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  9. Find the value of 'm'. If mx^3+ 2x^2- 3 and x^2- mx+ 4 leave the same ...

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  10. The polynomial px^(3)+4x^(2)-3x+q completely divisible by x^2-1: find ...

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  11. Find the number which should be added to x^2+ x +3 so that the resulti...

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  12. When the polynomial x^(3)+2x^(2)-5ax-7 is divided by (x - 1), the rema...

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  13. (3x + 5) is a factor of the polynomial (a-1)x^(3)+(a+1)x^2-(2a+1)x-15....

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  14. When divided by x- 3 the polynomials x^3-px^2+x+6 and 2x^3-x^2-(p+3)x-...

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  15. Use the Remainder Theorem to factorise the following expression 2x^(3)...

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  16. Using remainder theorem, find the value of k if on dividing 2x^3+ 3x^2...

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  17. What must be subtracted from 16x^3- 8x^2+4x+7 so that the resulting ex...

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