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Example Questions
Example Question #3 : How To Divide Exponents
If , then
Cannot be determined
Start by simplifying the numerator and denominator separately. In the numerator, (c3)2 is equal to c6. In the denominator, c2 * c4 equals c6 as well. Dividing the numerator by the denominator, c6/c6, gives an answer of 1, because the numerator and the denominator are the equivalent.
Example Question #3 : How To Divide Exponents
If , which of the following is equal to ?
a4
The answer cannot be determined from the above information
a18
a
a6
a18
The numerator is simplified to (by adding the exponents), then cube the result. a24/a6 can then be simplified to .
Example Question #3 : How To Divide Exponents
The easiest way to solve this is to simplify the fraction as much as possible. We can do this by factoring out the greatest common factor of the numerator and the denominator. In this case, the GCF is .
Now, we can cancel out the from the numerator and denominator and continue simplifying the expression.
Example Question #1 : Exponents
If (300)(400) = 12 * 10n, n =
12
3
7
4
2
4
(300)(400) = 120,000 or 12 * 104.
Example Question #2 : Exponents
(2x103) x (2x106) x (2x1012) = ?
8x1023
6x1021
8x1021
6x1023
8x1021
The three two multiply to become 8 and the powers of ten can be added to become 1021.
Example Question #65 : Exponents
Which of the following is equivalent to
and can be multiplied together to give you which is the first part of our answer. When you multiply exponents with the same base (in this case, ), you add the exponents. In this case, should give us because . The answer is
Example Question #2 : Exponents
If 3x = 27, then 22x = ?
32
64
9
8
3
64
- Solve for x in 3x = 27. x = 3 because 3 * 3 * 3 = 27.
- Since x = 3, one can substitute x for 3 in 22x
- Now, the expression is 22*3
- This expression can be interpreted as 22 * 22 * 22. Since 22 = 4, the expression can be simplified to become 4 * 4 * 4 = 64.
- You can also multiply the powers to simplify the expression. When you multiply the powers, you get 26, or 2 * 2 * 2 * 2 * 2 * 2
- 26 = 64.
Example Question #2 : Exponents
Find the value of x such that:
8x-3 = 164-x
7/2
4
11/3
19/4
25/7
25/7
In order to solve this equation, we first need to find a common base for the exponents. We know that 23 = 8 and 24 = 16, so it makes sense to use 2 as a common base, and then rewrite each side of the equation as a power of 2.
8x-3 = (23)x-3
We need to remember our property of exponents which says that (ab)c = abc.
Thus (23)x-3 = 23(x-3) = 23x - 9.
We can do the same thing with 164-x.
164-x = (24)4-x = 24(4-x) = 216-4x.
So now our equation becomes
23x - 9 = 216-4x
In order to solve this equation, the exponents have to be equal.
3x - 9 = 16 - 4x
Add 4x to both sides.
7x - 9 = 16
Add 9 to both sides.
7x = 25
Divide by 7.
x = 25/7.
Example Question #1 : Exponents
Which of the following is equal to 410 + 410 + 410 + 410 + 411?
250
260
223
215
240
223
We can start by rewriting 411 as 4 * 410. This will allow us to collect the like terms 410 into a single term.
410 + 410 + 410 + 410 + 411
= 410 + 410 + 410 + 410 + 4 * 410
= 8 * 410
Because the answer choices are written with a base of 2, we need to rewrite 8 and 4 using bases of two. Remember that 8 = 23, and 4 = 22.
8 * 410
= (23)(22)10
We also need to use the property of exponents that (ab)c = abc. We can rewrite (22)10 as 22x10 = 220.
(23)(22)10
= (23)(220)
Finally, we must use the property of exponents that ab * ac = ab+c.
(23)(220) = 223
The answer is 223.
Example Question #2 : Exponents
If 3 + 3n+3 = 81, what is 3n+2 ?
26
3
9
18
81
26
3 + 3n+3 = 81
In this equation, there is a common factor of 3, which can be factored out.
Thus, 3(1 + 3n+2) = 81
Note: when 3 is factored out of 3n+3, the result is 3n+2 because (3n+3 = 31 * 3n+2). Remember that exponents are added when common bases are multiplied. Also remember that 3 = 31.
3(1 + 3n+2) = 81
(1 + 3n+2) = 27
3n+2 = 26
Note: do not solve for n individually. But rather seek to solve what the problem asks for, namely 3n+2.
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