Question

How do you simplify a expression with positive exponents?

How do you write a fractions an expression using a negative exponent?

Answer 1

I'll try to answer the case I think you're asking about. If I'm guessing wrong, do ask again.

If you have something like x^2 * x^3 (x-squared times x-cubed) then you add the exponents:

x^2 * x^3 = x^5

Similarly, in general,

x^a * x^b = x^(a+b)


With negative exponents, you drop the negative bit, and write "one over" the expression, thus:

x^(-1) = 1/x

x^(-2) = 1/x^2

x^(-3.14159) = 1/x^3.14159

and in general

x^(-a) = 1/x^a

Answer 2

like, the scientific notation?

Answer 3

Yes, but "scientific notation" is often used when talking about powers of 10, like:

20000 = 2 * 10^4

This makes arithmetic with large numbers easy, since, following the rule above, all you have to do is add powers to multiply the factors of 10, like:

(2.1 * 10^5) * (3 * 10^4)

= 2.1 * 3 * 10^5 * 10^4

= 6.1 * 10^9

Answer 4

Oops: that last line should have been

= 6.3 * 10^9

of course!