Question

In the product of (3x³-5x²+6x-7) (ax²+2x+B) the coefficient of x⁴ is -4 and that of x is -32. Find a and B.

Answer 1

Answer:

basically

Step-by-step explanation:

Answer 2

In multiplication of variables, you add exponents if the variables are same.

So the exponent 4 is gained through 3+1, 2+2

And the exponent 1(x is x¹) is gained through 1+0, 0+1

Exponent 4

    3x³ × 2x = 6x⁴

+  -5x² × ax² = -5ax⁴

     -4x⁴         = -5ax⁴+6x⁴        

By comparing coeffieicient

→ -5a+6=-4

→ a=2

You can do exponent 1 in the same way. I hope it helps.

In this question, finding exponent sum is important. But try to understand the question, not memorize the answer. Surely it will help you solve more questions.