If the product of the roots of $4x^3 + 16x^2 - 9x - a = 0$ is $9$, then find $a$.

If the product of the roots of 4x³ + 16x² - 9x - a – Class 12 Mathematics

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4x^3 + 16x^2 - 9x - a = 0

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For a cubic $Ax^3+Bx^2+Cx+D=0$ , the product of the roots is $-D/A$ ; set that equal to 9 and solve for $a$ .

The equation is $4x^3+16x^2-9x-a=0$ , so comparing with $Ax^3+Bx^2+Cx+D=0$ : $A=4$ , $B=16$ , $C=-9$ , $D=-a$ .

For a cubic, the product of the roots (using Vieta's formulas) is

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