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# indicies .. watch

1. how do you do these can anyone write a step by step method please or a website I could find these on ?
2. To solve index equations, the first part is getting everything to the same base. E.g. 27^x = (3^3)^x = 3^3x. Once they're all the same base, if they're equal to each other, you can compare them.
3. For 1 and 2, there is only one value of x, so you can make x the subject of the equation and use a calculator to solve. For c and d, you want to make the bases equal so that you know the powers must be equal and can therefore make a simple equation
Hint:
For C, write 27^x in terms of 3 to the power of something using the fact that 27=3^3
4. wolframalpha is a pretty good site
5. (Original post by 3pointonefour)
To solve index equations, the first part is getting everything to the same base. E.g. 27^x = (3^3)^x = 3^3x. Once they're all the same base, if they're equal to each other, you can compare them.

how do you get the bases to be the same I'm confused with that ?
6. (Original post by Wildnatxox)
how do you get the bases to be the same I'm confused with that ?
Look at the smaller number and try to make the other numbers into a power of that number. So if we have 3 and 9, 3 is the smallest number so we can write 9 as 3^2.
7. (Original post by 3pointonefour)
Look at the smaller number and try to make the other numbers into a power of that number. So if we have 3 and 9, 3 is the smallest number so we can write 9 as 3^2.

so you look at the lowest common multiple ?
8. (Original post by Wildnatxox)
so you look at the lowest common multiple ?
Not the lowest common multiple - just the lowest number. And try to get the other numbers into powers of that smallest number.
9. (Original post by 3pointonefour)
Not the lowest common multiple - just the lowest number. And try to get the other numbers into powers of that smallest number.

does it matter what base number I chose to make the same?
10. (Original post by Wildnatxox)
does it matter what base number I chose to make the same?
Nope. As long as they're the same
11. (Original post by 3pointonefour)
Nope. As long as they're the same

how do you know what the answer is meant to be?
12. (Original post by Wildnatxox)
how do you know what the answer is meant to be?
Show me your working so I can see where you're at.

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Updated: April 26, 2018
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