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# C1 exponential equations

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1. How do you solve 9x = 3x + 2. ? It is in a C1 paper so you can't use logs.
2. (Original post by jessyjellytot14)
How do you solve 9x = 3x + 2. ? It is in a C1 paper so you can't use logs.
well you know that

we also know that
3. (3^2)^x = 3^x+2
4. You can use the property of injectivity: . It uses logs implicitly though.
5. .
6. 9^x is the same as 3^2x, so you get 3^2x = 3^(x+2)
From there, 2x = x+2
If you can't solve 2x = x+2, god help you, my friend.

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