Quick Question

Evaluate -a^2 (-a^2 = -a to the second power) for a= -5.3

The answer in the book is -28.09

My question: Why is the answer negative?

I think of this as -5.3 x -5.3 which would be a positive 5.3

Thanks for you time.

Mark

Evaluate -a^2 (-a^2 = -a to the second power) for a= -5.3

The answer in the book is -28.09

My question: Why is the answer negative?

I think of this as -5.3 x -5.3 which would be a positive 5.3

Click to expand...

It's all about how things are grouped with parentheses. In this case, there are no parentheses, so the negative sign is not being squared; only the "a" is squared.

If you write it as (-a)^2, then you will get a positive answer.

-a^2 really means: square a, then change the sign to the opposite.