How do you use the remainder theorem to find the remainder for the division (3t^3-10t^2+t-5)div(t-4)?

3 Answers
Jul 28, 2018

The remainder is 31.

Explanation:

Remainder Theorem :
When we divide a polynomial f(x) by (x−c) the remainder is f(c)
So to find the remainder after dividing by (x-c) we don't need to do any division: Just calculate f(c).

In this case,
f(4) = 3(4)^3 - 10(4)^2 + 4 - 5
f(4) = 31

Jul 28, 2018

The remainder is 31.

Explanation:

Note that the dividend is equal to the divisor times the quotient plus the remainder.

Let Q equal the quotient and R the remainder.

3t^3-10t^2+t-5=Q(t-4)+R

Notice that when t=4, the divisor t-4 becomes zero, meaning that anything multiplied to it will still result in zero.

Let's try t=4

=>3(4)^3-10(4)^2+(4)-5=Q(4-4)+R

=>192-160+4-5=R

=>31=R

That is the answer!

Jul 28, 2018

31

Explanation:

"the remainder when "f(x)" is divided by "(x-a)" is "f(a)

3(4)^3-10(4)^2+4-5=31larrcolor(blue)"remainder"