Let

be the identity matrix. Then pick whatever matrix you like for

.
Answer:

Step-by-step explanation:
By lowest terms, it means to simplify. You can do so by dividing the fraction by a common factor, which in this case, is 6:
÷
=

The fraction
cannot be simplified further, so this is the final answer.
4 = 2/4u
Multiply both sides by 4u
16u = 2
Divide both sides by 16, and simplify.
u = 1/8