Question

√-9 √-4 is equal ton​

Answer 1

Hey as we all know √a * √b = √a*b , but let's add little more knowledge to it.

The above mathematical equation (or rule) holds true only and only when atleast one of them is non-negative.

Now back to the given problem , here both are negative numbers {-9 , -4} . None of them are non-negative.

So we can't apply that rule here.

Therefore , √-9 *√-4 = √36 = {6 , -6 }will not give us proper answer.

And we also know √-1 = i (iota) which means

i^2 = -1

Now √-9 = 3i & √-4 = 2i

Now 3i * 2i = 6 i^2 = -6

√-9 *√-4 = -6.

So now we need to simplify them using complex numbers.