Question

I want to make sure I have these right. Below are the questions, and I marked the answers I did the work out for and think are right.

Factor completely p4 - 18p2 + 81
Choose one answer.
a. (p - 9)2
b. (p - 3)2(p + 3)2
c. (p2 - 9)(p2 + 9)
d. (p - 3)(p + 3)(p2 + 9) <-- my answer

hich of the following is the expansion of (x + 5)6?
Choose one answer.
a. x6 + 5x5 + 25x4 + 125x3 + 625x2 + 3125x + 15625
b. x6 + 30x5 + 375x4 + 2500x3 + 9375x2 + 18750x + 15625
c. x6 + 6x5 + 15x4 + 20x3 + 15x2 + 6x + 1
d. None of the above <-- my answer

Which of the following is the third term in the expa

Answer 1

Oh, whoops, the last one:

Which of the following is the third term in the expansion of (8 - x)3?
Choose one answer.
a. -512x3
b. -24x2 <-- My answer
c. 24x2
d. 512x3

Answer 2

first ones c

Answer 3

second ones a

Answer 4

Can you show me your work? If not, that's fine, haha. Just wanna see where I went wrong :/

Answer 5

use binomial theorem

Answer 6

^yep what hashir said

Answer 7

I was SO sure about the second one.

I can't, Hashir. I have to use Pascal's Triangle.

Answer 8

thts binomial theorem -_-

Answer 9

lol

Answer 10

agree

Answer 11

:P I didn't know that -- I've only ever heard it called Pascal's Triangle.

Answer 12

umm utilising pascal's triangle we arrive at binomial theorem so yh... anywho last one is c

Answer 13

x^6+6c1(x)^6-1(5)+6c2(x)6-2(5)^2+6c3(x)^6-3(5)^3+6c4(x)^6-4(5)^4+6c5(x)^6-5(5)^5+6c6(x)^6-6(5)^6
solve to get the answer