Final answer to the problem
Step-by-step Solution
Learn how to solve trigonometric integrals problems step by step online. Solve the trigonometric integral int(sec(3xy)^2)dy. We can solve the integral \int\sec\left(3xy\right)^2dy by applying integration by substitution method (also called U-Substitution). First, we must identify a section within the integral with a new variable (let's call it u), which when substituted makes the integral easier. We see that 3xy it's a good candidate for substitution. Let's define a variable u and assign it to the choosen part. Now, in order to rewrite dy in terms of du, we need to find the derivative of u. We need to calculate du, we can do that by deriving the equation above. Isolate dy in the previous equation. Substituting u and dy in the integral and simplify.
