Question

Find the remainder when f(x) is divided by (x - k)

f(x) = 8x^4 + 7x^3 + 5x^2 - 5x + 35; k = 4

Answer 1

use the remainder theorem,
remainder = f(4) = .... (just plug x=4)

Answer 2

4220

Answer 3

@RadEn 4220

Answer 4

Close

Answer 5

2591

Answer 6

What did you substitute for x?

Answer 7

4

Answer 8

yes, 2591

Answer 9

Yep

Answer 10

You can use synthetic division:
4 [ 8 7 5 -5 35 ]
32 156 644 2556
------------------------+
8 39 161 639 2591 <--- remainder

Explanation of synthetic division:

write out the coefficients of the powers of x, in the right order (8, 7, 5, -5 and 35)
Put 4 in front (the value of k)
the first coefficient, 8 goes straight down.
Multiply 4 with 8, put 32 in the next column. Add the numbers: 39
Multiply 4 with 39, put 156 in the next column. Adding gives 161.
Etc. the last number you get this way is the remainder!