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So now we can deal with stuff like ... |
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X2 = 64 |
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| What about stuff like this? | ||
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| Can we solve this one for X? | ||
| Sure. | ||
| In fact, | ||
| we can do it a couple of different ways ... | ||
| FIRST WAY | ||
| We know that ... | ||
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| So if ... | ||
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| We just substitute in the 6 ... | ||
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| So X equals 36. | ||
| That way works really nice | ||
| when the problems are easy. | ||
| But sometimes we need another way. | ||
| Remember that we can do most anything we want | ||
| on one side of the = | ||
| as long as we do the same thing to the other side. | ||
| So here's what we do ... | ||
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| We put an exponent of 2 on everything | ||
| on each side of the equation. | ||
| If we write out each side with multiplication | ||
| instead of exponents, | ||
| we get ... | ||
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| The same answer, | ||
| wonderful ! | ||
| Here's a very important point that you should see ... | ||
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| We can also show why ... | ||
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| Wanna see? | ||
| No? | ||
| Well here it is anyway ... | ||
| Just what does that last thing say? | ||
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| So what times itself equals X 2? | ||
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X |
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copyright 2005 Bruce Kirkpatrick |
