Here are the solutions for the problems in the image:

26. i. (3,5)

27. $A^{-1} = A - 2I$

28. The determinant (rendit n) is: $n! \quad \text{(for n = 2)}$

29. The vector $d$ is a linear combination of vectors $a$, $b$, and $c$, hence it is represented.

30. iii. $t = -1$

31. iv. $a = 0$

32. i. $D = 0$

If you have any further questions or need additional details, feel free to ask!

Follow-up questions:

1. Would you like a detailed explanation of any of the solutions provided?
2. Do you need help with similar matrix-related problems?
3. Would you like to explore the concept of determinant calculations in detail?
4. Should we explore more about linear combinations of vectors?
5. Are you interested in step-by-step solutions for the linear equation system?

Tip:

For systems of linear equations, always check for dependencies between equations to identify if they are consistent, dependent, or independent.