- #1
GreenPrint
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Hi,
I just had this idea pop into my head... Can you use a trig sub with a reference triangle who has sides equal to zero? or more like a value close to zero such as dx or da or something?
For example
integral 1/sqrt(9+dx^2) (dx)^2
would have a reference triangle were the hypotenuse is sqrt(9+dx^2)
one of the legs would be 3
the other leg would be dx
you then could express dx/sqrt(9+dx^2) as either csc(theta) or sec(theta) depending on what leg you set 3 be equal to...
integral 1/sqrt(9+dx^2) (dx)^2 = integral csc(theta) dx
I just had this idea pop into my head... Can you use a trig sub with a reference triangle who has sides equal to zero? or more like a value close to zero such as dx or da or something?
For example
integral 1/sqrt(9+dx^2) (dx)^2
would have a reference triangle were the hypotenuse is sqrt(9+dx^2)
one of the legs would be 3
the other leg would be dx
you then could express dx/sqrt(9+dx^2) as either csc(theta) or sec(theta) depending on what leg you set 3 be equal to...
integral 1/sqrt(9+dx^2) (dx)^2 = integral csc(theta) dx
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