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MEIRELES.

FAO: People who are SICK at Maths

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Can you answer these 5 questions for me please!They are multiple choiceimagebox_1179603252_r96.jpgimagebox_1179603315_r58.jpgShow me the working out if you can pleaseSafe.

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As soon as I come out of my GCSE Maths exam, that was the end of itThere's no need for me to affliate with it anymore

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dy/dx means differentiateDifferentiation of x^4 = 4x^3 (you minus 1 from the power, and put the original power before the x)6x = 6 (minus 1 power from x so it's x^0, which = 1)1/x^2 is the same as x^-2, so becomes -2x^-3, which is -2/x^3

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7 is cif ur doin these sort of questions u must have an idea of how to work it out
I dont understand these questions thats why im asking lol
3 is b4 is bthose are the only ones i could do in my head at the moment
I BEG YOU TWO SHOW ME THE WORKING OUT

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okin integration, u take the power and add 1 to it. so for x^3 ----> x^4 BUT u multiply it by a 1/4 because intergration is the reverse of integrationto differentiate u multiply x by the power an take one away from the power1/4 multiplied by 4 = 1 and 4-1=3 so then u are back to ur original answer, apply this to the rest of question 7Number 6 is using the chain rule, you multiply the whole bracket by the power and take 1 away as with normal differentiation but u MUST multiply the answer by the differential of the bracket WHICH IS COSx

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7 = cYou're integrating, so you put add 1 to the power and put the new power under xSo x^3 becomes x^3/4 (or 1/4x^3)x^5 becomes x^6/6And you always add +c at the end of integration

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4 is that is the product ruleyou split the equation into two parts x^2 and cosxyou differentiate one of them an multiply it by the other you then do it the other way round so u differentiate the one u didn do in the first place an multiply it to the original of the other one then u add them togetherim goin to do my own work nowi hope that was a help im rubbish at explainin stuff

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4 is that is the product ruleyou split the equation into two parts x^2 and cosxyou differentiate one of them an multiply it by the other you then do it the other way round so u differentiate the one u didn do in the first place an multiply it to the original of the other one then u add them togetherim goin to do my own work nowi hope that was a help im rubbish at explainin stuff
4 is B?
Number 6 is using the chain rule, you multiply the whole bracket by the power and take 1 away as with normal differentiation but u MUST multiply the answer by the differential of the bracket WHICH IS COSx
So the answer to 6 is D?Thanks for the help still
This sh*t's easy biggrin.gif .
Answer 4, 6 and 46 for me then with working outSafe

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Dont you know about differentiation and integration? Surely you musta been taught it if you're gettin set the work...It's difficult to explain the technique of it online, Smaddy did it well, also look in your textbook or Wikipedia/Google searchBut the answers are:3.) cy = x^4 + 6x + 1/x^2 = x^4 + 6x + 1x^-2Dy/dx = 4x^3 + 6 + -2x-3 = 4x^3 + 6 + -2/x^34.) bf(x) = a(x)b(x)f'(x) = a'(x)b(x) + a(x)b'(x)Thus Dy/Dx = 2xcosx + x^2(-sinx) = 2xcosx - x^2(sinx)6.) there's no option for the correct answer, which isDy/dx = 5(Sinx + 1)^4 x cosx = 5cosx(sinx)^47.) c1/4(x^4) + 1/6(x^6) + c46.) ei represents the imaginary unit (-1)^(1/2) [e.g, the square root of -1]Any expression with this in, is a complex numberThey want the real expression (e.g. a non-complex one)So you find the expression which doesn't have "i" in itz + w = x + iy + x - iy = 2xSo the answers (e) ---> z + w

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SuperstitionSmaddyShabby All goons/goonettes.Safe for the helpMuch appreciated. biggrin.gifPS: Superstition.. The answer you go to 3 is B but you put C :S

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