This image contains several mathematical problems, specifically focusing on topics like matrix operations, systems of linear equations, trigonometric identities, and integrals. Let's address each of them:

Problem Breakdown:

1. Matrix Operations (Task 3) The first task involves performing matrix operations, particularly matrix addition and multiplication. The matrix equation given is:

   5 & 2 \\ 4 & 2 \end{bmatrix} \times \begin{bmatrix} 2 & 0 \\ 4 & 0 \end{bmatrix}$$ You are likely asked to compute the product of these matrices. I can help you work through this if needed.

2. Solving Linear Systems (Task 4) You are asked to solve the system of linear equations:

   2x + 3y = 5 \\ x + 4y = 3 \end{cases}$$ This is a basic system of two linear equations in two variables. We can solve this using substitution or elimination methods.

3. Integration Problems (Task 5) This involves finding specific integrals:

   • Part a): $\int \frac{5}{\cos(x)} \, dx$
   • Part b): $\int \frac{1}{\sqrt{2 - \sin^2(x)}} \, dx$

4. Trigonometric Identity Simplification (Task 6) You are asked to simplify the expression $\cos^2(x) - \sin^2(x)$, which is a common trigonometric identity.

Would you like detailed solutions or explanations for any specific part of this? Feel free to point out which task interests you most!