ACT Math : Exponential Operations

Study concepts, example questions & explanations for ACT Math

varsity tutors app store varsity tutors android store varsity tutors amazon store varsity tutors ibooks store

Example Questions

Example Question #6 :How To Add Exponents

Simplify: hn+ h–2n

Possible Answers:

Correct answer:

Explanation:

h–2n= 1/h2n

hn+ h–2n= hn+ 1/h2n

Example Question #7 :How To Add Exponents

Simplify: 3y2+ 7y2+ 9y3.– y3.+ y

Possible Answers:

10 y2+ 10y3.+ y

19y11

10 y2+ 9y3.

10 y4+ 8y6+ y

10 y2+ 8y3.+ y

Correct answer:

10 y2+ 8y3.+ y

Explanation:

Add the coefficients of similar variables (y, y2, 9y3.)

3.y2+ 7y2+ 9y3.– y3.+ y =

(3 + 7)y2+ (9 – 1)y3.+ y =

10 y2+ 8y3.+ y

Example Question #8 :How To Add Exponents

Simplify the following:

Possible Answers:

Correct answer:

Explanation:

When common variables have exponents that are multiplied, their exponents are added. SoK3.*K4=K(3.+4)=K7. AndM6*M2=M(6+2)=M8. So the answer isK7/M8.

Example Question #9 :How To Add Exponents

Solve for:

Possible Answers:

Correct answer:

Explanation:

First, reduce all values to a common base using properties of exponents.

Plugging back into the equation-

Using the formula

We can reduce our equation to

So,

Example Question #4 :Exponential Operations

Simplify: y3.x4(yx3.+ y2x2+ y15+ x22)

Possible Answers:

y3.x12+ y6x8+ y45x4+ y3.x88

y4x7+ y5x6+ y18x4+ y3.x26

y3.x12+ y6x8+ y45+ x88

y3.x12+ y12x8+ y24x4+ y3.x23

2x4y4+ 7y15+ 7x22

Correct answer:

y4x7+ y5x6+ y18x4+ y3.x26

Explanation:

When you multiply exponents, you add the common bases:

y4x7+ y5x6+ y18x4+ y3.x26

Example Question #6 :Exponential Operations

If, what is the value of?

Possible Answers:

Correct answer:

Explanation:

Rewrite the term on the left as a product. Remember that negative exponents shift their position in a fraction (denominator to numerator).

The term on the right can be rewritten, as 27 is equal to 3 to the third power.

Exponent rules dictate that multiplying terms allows us to add their exponents, while one term raised to another allows us to multiply exponents.

We now know that the exponents must be equal, and can solve for.

Example Question #11 :Exponential Operations

If, what is the value of?

Possible Answers:

Correct answer:

Explanation:

Since the base is 5 for each term, we can say 2 + n =12. Solve the equation for n by subtracting 2 from both sides to get n = 10.

Example Question #41 :Exponents

Which expression is equivalent to the following?

Possible Answers:

None of these

Correct answer:

None of these

Explanation:

The rule for adding exponents is. We can thus see thatandare no more compatible for addition thanandare.

Youcouldcombine the first two terms into, but note that PEMDAS prevents us from equating this to(the exponent must solve before the distribution).

Example Question #42 :Exponents

Express as a power of 2:

Possible Answers:

The expression cannot be rephrased as a power of 2.

Correct answer:

Explanation:

Since the problem requires us to finish in a power of 2, it's easiest to begin by reducing all terms to powers of 2. Fortunately, we do not need to use logarithms to do so here.

Thus,

Example Question #43 :Exponents

Simplify the following expression:

Possible Answers:

Correct answer:

Explanation:

When multiplying bases that have exponents, simply add the exponents. Note that you can only add the exponents if the bases are the same. Thus:

Learning Tools by Varsity Tutors