WEBVTT
1
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all right, we have function h of X.
2
00:00:06.040 --> 00:00:08.400 A:middle L:90%
And according to the problem, H of X is
3
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the composition of G of F. So f is
4
00:00:11.769 --> 00:00:14.330 A:middle L:90%
the inside function, and we know that we need
5
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to find the outside function and somehow there's a times
6
00:00:17.370 --> 00:00:19.620 A:middle L:90%
for involved. So let's do a little bit of
7
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playing around with it. So what if g of
8
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x waas just for X, what would we get
9
00:00:28.820 --> 00:00:34.039 A:middle L:90%
for GFF? We would get four times the quantity
10
00:00:34.049 --> 00:00:37.719 A:middle L:90%
X plus four, so that would be four times
11
00:00:37.719 --> 00:00:41.090 A:middle L:90%
X plus 16. Well, that's not quite right
12
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because we wanted four times X minus one. We
13
00:00:44.560 --> 00:00:48.250 A:middle L:90%
have plus 16. So this answer is 17 too
14
00:00:48.259 --> 00:00:51.659 A:middle L:90%
large. So what if we then compensated for that
15
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by subtracting 17 in our G of X? That
16
00:00:58.759 --> 00:01:02.799 A:middle L:90%
would give us for X minus one. So that
17
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means that G of X must be for X minus
18
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17 so that we can substitute X plus four into
19
00:01:08.319 --> 00:01:11.349 A:middle L:90%
it and end up with age of X