Recent content by chewy

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    Calculating Length of Line from y=1 to y=3

    ahh, i see, i was taking it too literaly, thks very much
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    Calculating Length of Line from y=1 to y=3

    ok i see, thks, but I am still confused on how 1 + (dy/dx)^2 is a perfect square, doesn't there need to be a third term??
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    Calculating Length of Line from y=1 to y=3

    ok, i found the derivative first which was y^2 - 1/(4y^2), i then squared this which gave me y^4 + 1/(16y^4) - 1/2, i then stuck this in the formula and added the one, which gave y^4 +1/(16y^4) + 1/2, i then put the terms together (16y^8 + 8y^4 + 1)/16y^4, i then seen the numerator is the a...
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    Find th length of th line x = int sqrt(sec(t)^4 - 1)) from 0 to y

    sorry that was meant to be y is equal or more than -pi/4 and y is equal or less that pi/4
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    Find th length of th line x = int sqrt(sec(t)^4 - 1)) from 0 to y

    Homework Statement definate integral to find length of line x = int [sqrt( (sec t)^4 - 1) integrate from 0 to y with -pi/4 < y > pi/4 it is actually y is equal or more/less than pi/4 The Attempt at a Solution Ive worked out that the length of the line will be the same...
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    Calculating Length of Line from y=1 to y=3

    Find the length of which line ? The equation you have posted will graph out to be a complex curve! the line will be continuous from y =1 to y= 3, not quite sure what u mean, there is only one line x = (y^3/3) + 1/(4y).
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    Calculating Length of Line from y=1 to y=3

    The formula for length of a line y = f(x) Length = int [sqrt(1+ (dx/dy)^2)] dx in this case the variable is y,
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    Calculating Length of Line from y=1 to y=3

    ok, i found the derivative first which was y^2 - 1/(4y^2), i then squared this which gave me y^4 + 1/(16y^4) - 1/2, i then stuck this in the formula and added the one, which gave y^4 +1/(16y^4) + 1/2, i then put the terms together (16y^8 + 8y^4 + 1)/16y^4, i then seen the numerator is the a...
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    Calculating Length of Line from y=1 to y=3

    Homework Statement finding the lengths of a line Homework Equations x = (y^3/3) + 1/(4y) from y =1 to y=3 hint:: 1 + (dx/dy)^2 is a perfect square The Attempt at a Solution I found the solution, i did this by just finding the derivative and then putting it into the equation for...
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    Proving Definite Integral Using Substitution | Solving Math Problem

    thks very much, I've learned more of these two questions, than the previous easier 30.
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    Proving Definite Integral Using Substitution | Solving Math Problem

    Homework Statement prove by substitution that definite integral int (1/t)dt from [x to x*y] = int (1/t)dt from [1 to y]. Homework Equations The Attempt at a Solution i can do this problem if i integrate and use the log laws, no probs, but the question says to use a substitution...
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    How do I solve this tricky calculus substitution question?

    forget that last reply, i figured it out this morning when i woke with a fresh head. the graphs have the same area but the new one comes from the other side, when f(x) = 0, then f(a-x)= a, when f(x)= a the f(a-x) = 0. painfully obvious now. this is website is a great idea, thanks again for...
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    How do I solve this tricky calculus substitution question?

    thanks very much for the reply, i followed your advice and the integrand i had was 1, which in turn leads to a when integrated, I am a little confused over the dummy variable, is u=x because the limits of the integrand are still [0-a] when reversed? also the answer in the book is a/2, does this...
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    How do I solve this tricky calculus substitution question?

    Homework Statement if f is a continuous function, find the value of the integral I = definte integral int [ f(x) / f(x) + f(a-x) ] dx from 0 to a. by making the substitution u = a - x and adding the resulting integral to I. this is one of the last questions in the thomas international...
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