Question

In the expression (x + y)^8, if x = 0.3 and y = 0.7, what is the numerical value of the third term?
a. 0.010
b. 0.020
c. 0.058
d. 0.060
e. 0.068

Answer 1

What do you think it is?

Answer 2

uh

Answer 3

a?

Answer 4

What do you think it is?

Answer 5

what is the formula for the third term?

Answer 6

idk

Answer 7

do you understand what the statement is asking you to look at?

Answer 8

no?

Answer 9

I think they have Newton's binomial formula in mind. Have you studied this already?

Answer 10

nope

Answer 11

Then you cannot answer the question…
https://en.wikipedia.org/wiki/Binomial_theorem

According to this formula, the 3rd term will be \[ C^8_2 (0.3)^6 (0.7)^2 = 28 (0.3)^6 (0.7)^2= 0.01000188\]

Answer 12

oh so i was right

Answer 13

How did you find it?

Answer 14

just a guess tbh

Answer 15

I encourage you to learn Newton's formula, it's a great one.. and useful.