6all over 9 i=?????? help please

Question

or help on this question 7i x 8i=?????????

Answer 1

7i x 8i = 56i

Answer 2

The problem with 6/(9i) (assuming the i to be in the denominator) is that you aren't allowed to have an imaginary in the denominator.  (It's a special case of the "no roots in the denominator" rule.)  First, reduce it to

2/(3i)

Then multiply by i/i:

2i/(3i^2) = -2i/3

Answer 3

Jessie, actually that's incorrect.

7i x 8i = 56i^2 = 56 x -1 = -56