I need to calculate the area of a figure that is bounded by lines
$$\rho=\cos(\varphi),\quad \rho=\sqrt{2}\cos(\varphi-\pi/4),\quad (-\pi/4 ≤ \varphi ≤ \pi/2)$$
Initially, I assumed that the first function is greater than the second and subtracted their squares with given boundaries. But then I set the bound from 0 to 1. I got confused about the boundary of my integral and function. Could you give me a lead?