Question

What is the fourth term of (a - sqrt(2))^8

Answer 1

Mechanical hint.
a 8 \(\sqrt{2}\) 0
a 7 \(\sqrt{2}\) 1
a 6 \(\sqrt{2}\) 2
a 5 \(\sqrt{2}\) 3

Answer 2

i guess i dont know what that means ..

Answer 3

You probably have a fancy formula for each specific term. You should use that.

\({8\choose{n}}x^{n}y^{8-n} = (x + y)^{8}\)

That may be convenient to find the 133rd term from a 3645-term expansion. None terms? Just write them all out.

\({8\choose{0}}\) a 8 \(\sqrt{2}\) 0
\({8\choose{1}}\) a 7 \(\sqrt{2}\) 1
\({8\choose{2}}\) a 6 \(\sqrt{2}\) 2
\({8\choose{3}}\) a 5 \(\sqrt{2}\) 3

Almost done!

Answer 4

* nine

Answer 5

(8 n )x n y 8−n =(x+y) 8

Of course, I meant \((x+y)^{8} = \sum_{n=0}^{8} {{8}\choose{n}}x^{8-n}y^{n}\)

Bad typing!