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...
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...
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).
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...
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...
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...
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...
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...
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...