Find th length of th line x = int sqrt(sec(t)^4 - 1)) from 0 to y

[chewy]

Homework Statement

definite 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 from -pi/4 to 0 as 0 to pi/4,
giving me

x = 2*int(sqrt( (sec t)^4 - 1)
integrating from 0 to pi/4,
im struggling with the integral, i know it must be substitution and i ve tried numerous trig identities just been coming up blank so far. a little push in the right direction would be great

 

[chewy]

sorry that was meant to be y is equal or more than -pi/4 and y is equal or less that pi/4

 

[chewy]

dont worry about it i figured it out