00:01
Okay, this problem is to compete the expansion of 5 minus x squared all to the power 5.
00:06
So comparing this to our standard binomial of a plus b to the power n.
00:10
We see that the a is 5, the b is negative x, and the n is 5.
00:15
So we'll be using the fifth row of our pascal's triangle right here in a minute.
00:19
Okay, let's get this going.
00:21
So something from the pascal's triangle, 5 to the power 5.
00:26
Something from the pascal's triangle, 5 to the power 4, negative x squared to the power 1.
00:33
Yeah, we're just dropping the exponent on the first parentheses and increasing the exponent on the second parentheses.
00:41
Okay, making sure they always add up to 5.
00:45
Okay, and we just keep this pattern going.
00:48
5 to the power 1, negative x squared to the power 4.
00:52
Okay, the last term, 5 to the power 0, we know that's 1 so we don't need that.
00:57
I'm just going to have negative x squared to the power 5...