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Maths question problem (1 Viewer)

Roy216

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Hey guys I am unsure how to do question 10 i).

I used simultaneous equations but the answers did something else

can anyone help?

Untitled.jpg
 

iBibah

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Writing a solution in latex for you now (soz im a bit slow)
 

iBibah

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After finding k, do you know how to find the initial intensity?
 

Roy216

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yeah thanks after that I'm good, just want to know why you divided (1) by (2)? thats what the answers had

i tried to work it out by using simultenous equations
 

iBibah

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yeah thanks after that I'm good, just want to know why you divided (1) by (2)? thats what the answers had

i tried to work it out by using simultenous equations
I also used simultaneous equations. Because I and k are the same in both, just like x and y in your standard simultaneous equation. So really you could have done anything you do to any other simultaneous question, and dividing was the best option to eliminate I
 

Roy216

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really? i tried making Io the subject for one of the equations then subing it into another, but that didn't seen to work
 

Roy216

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ok i understand that, but how would you know when one kind is better then the other, because there are many different ways to do simultaneous equations
 

Sy123

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The best way to do a math exam, is actually knowing what you are doing rather than blindly following standard process, being able to find a clever substitution or algebra technique is a skill that is highly needed for math.
 

iBibah

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really? i tried making Io the subject for one of the equations then subing it into another, but that didn't seen to work
That also works:



Though the other way is probably quicker.
 

Roy216

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The best way to do a math exam, is actually knowing what you are doing rather than blindly following standard process, being able to find a clever substitution or algebra technique is a skill that is highly needed for math.
I do know what I'm doing, but I've never seen the division simulatenous equation before. Its new to me.
 

iBibah

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I do know what I'm doing, but I've never seen the division simulatenous equation before. Its new to me.
You might have used it when doing geometric progression questions where you are given two terms (i.e 3rd and 7th) and you have to find the common ratio and first term.
 

Roy216

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You might have used it when doing geometric progression questions where you are given two terms (i.e 3rd and 7th) and you have to find the common ratio and first term.
Yeah i remember that, ah that too is a simultaneous equation
 

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