Determine which of the following formulas hold for all invertible ×n×n matrices A and B. 1. =AB=BA 2. +A+B is invertible 3. (+)2=2+2+2(A+B)2=A2+B2+2AB 4. (+)(+−1)=2++−1(I+A)(I+A−1)=2I+A+A−1 5. (−)(+)=−2(I−A)(I+A)=I−A2 6. ()−1=−1−1(AB)−1=A−1B−1 7. 3A3 is invertible 8. (−1)3=3−1(ABA−1)3=AB3A−1 9. −1=ABA−1=B 10. (+)(−)=2−2

Acircle has a circumference of 2 pi cm. which statement about the circumference and area is true? a comparison of the area and circumference is not possible since the area cannot be determined. the numerical values of the circumference and area of the circle are equal. the numerical value of the circumference is greater than the numerical value of the area. the numerical value of the circumference is less than the numerical value of the area.

An angle that measures between 90 and 180° is called a(,

Write an expression that represent sarah’s total pay last week. represent her hourly wage with w monday 5 tuesday 3 wednesday 0 noah hours wednesday 8 only with w wage did noah and sarah earn the same amount last week?