document.write( "Question 366198: Evening All, Right its been a while since i have attempted maths, and have just gone back to further ed. I have attempted the following questions, which im sure should be simple, but of course like anything its just getting back into things after a number of years. i have listed the questions below, and my answers if anybody will take the time to have a quick look and correct me where neccessary i would appreciate this.\r
\n" ); document.write( "\n" ); document.write( "1)Find dy/dx by differentiating with respect to x the following expressions.\r
\n" ); document.write( "\n" ); document.write( "a) y=x^3-6x^2+9x-1 = 3x^2-12x+8
\n" ); document.write( "b) y=1/2x -sqrtx = 1/2-1/2x^-1/2
\n" ); document.write( "c) y=e^x-e^-x = e^x+e^-x
\n" ); document.write( "d) y=25cosx--sinx = -25sinx-cosx
\n" ); document.write( "e) y= 3sinhx-4coshx = 3hsinhx+4hsinhx
\n" ); document.write( "f) y= (x^2+1) sinhx = 1\r
\n" ); document.write( "\n" ); document.write( "2 Use product rule to obtain dy/dx for the following\r
\n" ); document.write( "\n" ); document.write( "a) y=x^2e^x = 2x(e^x)+x^2(e^x)
\n" ); document.write( "b) y= xtanx = 1(tanx)+x(sec^2x)
\n" ); document.write( "c) y= x^4ln(x)= 4x^3(ln(x))+x^4(1/x)
\n" ); document.write( "d) y= x^2sinx = 2x(sinx)+x^2(cosx)
\n" ); document.write( "e) y= e^-xcosx = -e^-x(cos x)+ e^-x (-sinx)
\n" ); document.write( "f) y=(x^2+1)sinhx = (2x +1) (sinhx)+(x^2+1)(cosh x)\r
\n" ); document.write( "\n" ); document.write( "Finally, use the quotient rule to differentiate with respect to x, simplifying as far as possible.
\n" ); document.write( "a) y= sinx/1+e^-x = 1+e^-x(cpsx)-(1-e^x)sinx/(1+e^-x)^2\r
\n" ); document.write( "\n" ); document.write( "b) y= lnx/1+x^2 = 1+x^2(1/x)-1+2x(ln x)/(1+x^2)^2\r
\n" ); document.write( "\n" ); document.write( "Really this would be appreciated thank you
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Algebra.Com's Answer #261237 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
1a)\"dy%2Fdx=3x%5E2-12x%2Bhighlight%289%29\"
\n" ); document.write( "b) Correct!
\n" ); document.write( "c) Correct!
\n" ); document.write( "d) Correct!
\n" ); document.write( "e)\"dy%2Fdx=3%2Asinh%28x%29%2B4%2Asinh%28x%29\"
\n" ); document.write( "I think you misinterpreted as \"sin%28hx%29\" when it's actually the hyperbolic sine function, \"sinh%28x%29\", same for the cosine.
\n" ); document.write( "f)\"dy%2Fdx=%28x%5E2%2B1%29cosh%28x%29%2B%282x%29sinh%28x%29\"
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\n" ); document.write( "2a) Correct! Could be simplified to \"dy%2Fdx=e%5Ex%28x%2B2%29\"
\n" ); document.write( "b) Correct!
\n" ); document.write( "c) Correct! Could be simplified to \"dy%2Fdx=4x%5E3%28ln%28x%29%2B1%29\"
\n" ); document.write( "d) Correct!
\n" ); document.write( "e) Correct! Could be simplified to \"dy%2Fdx=-e%5E%28-x%29%28cos%28x%29+%2Bsin%28x%29%29\"
\n" ); document.write( "f) Correct! but why weren't your answers for 1f and 2f the same??
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\n" ); document.write( "3a)
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\n" ); document.write( "b) \"dy%2Fdx=+%28%281%2Bx%5E2%29%281%2Fx%29-ln%28x%29%282x%29%29%2F%281%2Bx%5E2%29%5E2\"
\n" ); document.write( "\"dy%2Fdx=+%28%281%2Bx%5E2%29-2x%5E2ln%28x%29%29%2F%28x%281%2Bx%5E2%29%5E2%29\"
\n" ); document.write( "\"dy%2Fdx=%28x%5E2-2x%5E2ln%28x%29%2B1%29%2F%28x%28x%5E2%2B1%29%5E2%29\"
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