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# Quick C1 equation Q watch

1. Would 3^(x+2) be y * 3^2 = 9y
and 3^(1-x) be -y * 3 = -3y

therefore 9y - 3y = 12 => 6y = 12 => y=2 => 3^x=2

or have I got this wrong
2. You know that and

How can you use that to break up and

3. (Original post by Ben121)
You know that and

How can you use that to break up and

3^(1-x) = 3/y = 3y^(-1)

therefore for b) 9y + 3y^-1 = 12
which solves down to (9y-3)(y-1)=0 (after multiplying by y, re-organizing it and factorising), which solves to give 1/3 or 1 as answer?
4. That gives you y = 1/3 or y = 1.

Substitute that into y = 3^x and solve for x.
5. (Original post by Ben121)
That gives you y = 1/3 or y = 1.

Substitute that into y = 3^x and solve for x.
1 = 3^x, therefore x=0
1/3 = 3^x, therefore x=-1

right? thankyou
6. Correct

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Updated: March 20, 2011
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