# Math Help - exponent Question

1. ## exponent Question

this is confusing me,

my teacher wrote an answer as

4.5 x 10^17

my calculator shows it as 4.5^17

how is that the same thing?

question is find energy "e"
info is given and you get

e=5(3 x 10^8)^2

could someone please explain the difference of
4.5 x 10^17
and
4.5^17

and why when I type 10^17 into my calculator and press = does it show 1^17 ?
Thanks.

2. Originally Posted by brentwoodbc
this is confusing me,

my teacher wrote an answer as

4.5 x 10^17

my calculator shows it as 4.5^17

how is that the same thing?

question is find energy "e"
info is given and you get

e=5(3 x 10^8)^2

could someone please explain the difference of
4.5 x 10^17
and
4.5^17

Thanks.
$4.5 \times 10^{17} = 4.5 \times 10 \times 10 \times 10 \times 10....$ $\text{and so on... 17 times! Which is equivalent to 45 with 16 zeros after it!}$

$4.5^{17} = 4.5 \times 4.5 \times 4.5 \times 4.5 \times 4.5.... \text{and so on... 17 times!}$

$\text{They are very different.}$

$\text{To answer your energy question:}$

$e = 5(3\times 10^8)^2$

$e = 5(3^2 \times (10^8)^2)$

$e = 5(9 \times 10^{16})$

$e = 45 \times 10^{16}$

$e = 4.5 \times 10^{17}$

3. so which is right for this question? he wrote 4.5x10^17
he always does that number x10^number

4. 4.5 x 10^17 is correct and mush check your error

5. Originally Posted by brentwoodbc
so which is right for this question? he wrote 4.5x10^17
he always does that number x10^number
See previous posts!

4.5 x 10^17 is correct and mush check your error
why does my calculator show 4.5 E17 then?

7. Originally Posted by brentwoodbc
why does my calculator show 4.5 E17 then?
E signifies "times 10 to the power of!"

$4.5 E17 = 4.5 \times 10^{17}$

8. Originally Posted by brentwoodbc
why does my calculator show 4.5 E17 then?
The notation means
4.5E17 = 4.5 x 10^17

9. Originally Posted by Mush
E signifies "times 10 to the power of!"

$4.5 E17 = 4.5 \times 10^{17}$
and on standard scientific caculators the exponent is x10^ also?

EDIT
ok ok of course it does, sorrey Im very tired and just got back from night school, thanks for the help.

10. Originally Posted by brentwoodbc
and on standard scientific caculators the exponent is x10^ also?
Check my pictures. The button with the red circle is used for $4.5^{17}$ whilst the button in the blue circle is used for $4.5\times 10^{17}$

To get $4.5^{17}$:

Hit the 4 key.
Hit the . key.
Hit the 5 key.
Hit the red circle key.
hit the ( key.
Hit the 1 key.
Hit the 7 key.
Hit the ) key.
Hit = key.

To get $4.5\times 10^{17}$:

Hit the 4 key.
Hit the . key.
Hit the 5 key.
Hit the blue circle key.
hit the ( key.
Hit the 1 key.
Hit the 7 key.
Hit the ) key.
Hit = key.

11. Originally Posted by Mush
Check my pictures. The button with the red circle is used for $4.5^{17}$ whilst the button in the blue circle is used for $4.5\times 10^{17}$

To get $4.5^{17}$:

Hit the 4 key.
Hit the . key.
Hit the 5 key.
Hit the red circle key.
hit the ( key.
Hit the 1 key.
Hit the 7 key.
Hit the ) key.
Hit = key.

To get $4.5\times 10^{17}$:

Hit the 4 key.
Hit the . key.
Hit the 5 key.
Hit the blue circle key.
hit the ( key.
Hit the 1 key.
Hit the 7 key.
Hit the ) key.
Hit = key.
awesome ya thats right,
so $4.5^{17}$ is equal to $1.27$ x $10^{11}$ right?

12. Originally Posted by brentwoodbc
awesome ya thats right,
so $4.5^{17}$ is equal to $1.27$ x $10^{11}$ right?
Approximately to a very large extent