I am having trouble understanding this... I can't remember whose notes this is from, but it is something I printed off this site.

7^4 + 7^7

= 7^4(1+7^3)

=7^4(50)

And

3^4+12^4

=3^4+ (3*4)^4

=3^4(1+4^4)

=3^4(256)

In both instances I am confused with what happens to the one in the second to last step. Wouldn't it be 3^4+3^4(256)? It seems like the 1 just disappears???

Here is a problem I can not solve:

2^x - 2^x-2 = 3(2^13)

x=?

The answer is 15 but I do not understand how to get it. Is there a good guide online or does someone have good notes for exponents? I am lacking in this area and I need it dumbed down.

1.

2.

(so again the answer given in your example is not correct).

A. 9

B. 11

C. 13

D. 15

E. 17

.

Answer: D.