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# How do i solve this equation?? C2

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1. 4x-480x^-2=0
howq do i solve? step by step? Thanks all!
2. try multiplying by x^2
3. (Original post by Coulson72)
try multiplying by x^2
Okay sweet I got : 4x^3-480=0
4x^3=480
x^3=120
x= 3 root 120 = 4.9...
Thanks alot btw, but how do I choose what to multiply by if this was another q in an exam with different multiples...? Thanks though!!
4. well if you get summit similar try multiplying by enough to turn the biggest negative into a 0, so like if you have 2x^2+5x^-3=0 then you'd try multiplying by x^3 to turn the -3 into a 0
5. (Original post by alex7892)
Okay sweet I got : 4x^3-480=0
4x^3=480
x^3=120
x= 3 root 120 = 4.9...
Thanks alot btw, but how do I choose what to multiply by if this was another q in an exam with different multiples...? Thanks though!!
Well it's better to get rid of the fractions or negative power (by this I mean or ). So multiply by whatever you need to get rid of the negative power.
6. Thanks all great help. Love feeling confident about maths and getting it haha!!
7. (Original post by alex7892)
Okay sweet I got : but how do I choose what to multiply by if this was another q in an exam with different multiples...? Thanks though!!
Suppose you have been given permission to drive your friends car. You are given a large bunch of keys. How do you KNOW which key to use?

What would you do? I guess most people would try one key, then another and so on.

It's the same with mathematics. JUST try and see what happens.

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