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| | 16 Theory slides |
| | 10 Exercises - Grade E - A |
| | Each lesson is meant to take 1-2 classroom sessions |
Here are a few practice exercises before getting started with this lesson.
Consider the following algebraic expression. sqrt(8x^3) * (x^(12)y)^5/sqrt(2x^2y)* x^(13)
Can the above expression be written using only rational exponents? Using only radicals?The following table shows the Properties of Exponents.
| Product of Powers Property | a^m a^n = a^(m+n) |
|---|---|
| Quotient of Powers Property | a^m/a^n= a^(m-n) |
| Power of a Product Property | (ab)^n=a^nb^n |
| Power of a Quotient Property | (a/b)^n = a^n/b^n |
| Power of a Power Property | (a^m)^n=a^(m* n) |
The multiplication of two powers with the same base a and rational exponents m and n results in a power with base a and exponent m+n.
Recall that p and q are integer numbers. Therefore, the Product of Powers Property can be used. sqrt(a^p * a^q) = sqrt(a^(p+q)) The resulting expression can be written using only exponents.
It has been proven that a^m* a^n=a^(m+n) for rational numbers m and n.
The quotient of two powers with same base a and rational exponents m and n results in a power with base a and exponent m-n.
Recall that p and q are integer numbers. Therefore, the Quotient of Powers Property can be used. sqrt(a^p/a^q) = sqrt(a^(p-q)) The resulting expression can be written using only exponents.
It has been proven that a^ma^n=a^(m-n) for rational numbers m and n.
Multiplying two numbers or variables and then raising the product to the power of n, where n is rational, is the same as raising the factors to the power of n and then multiplying them.
Recall that p is an integer number. Therefore, the Power of a Product Property can be used to rewrite the expression. sqrt((ab)^p) = sqrt(a^pb^p) The index of the above radical is an integer number, q. Therefore, the obtained expression can be rewritten as the product of two radicals. Then, the definition of a rational exponent can be used.
sqrt(a* b)=sqrt(a)*sqrt(b)
sqrt(a^m)=a^(mn)
p/q= n
It has been proven that (ab)^n=a^nb^n for rational n.
Dividing two numbers or variables and then raising the quotient to the power of n, where n is rational, is the same as raising the divisor and dividend to the power of n and then calculating the quotient.
Recall that p is an integer number. Therefore, the Power of a Quotient Property can be used to rewrite the expression. sqrt((a/b)^p) = sqrt(a^p/b^p) The index q of the above radical is an integer number. Therefore, the obtained expression can be rewritten as the quotient of two radicals. Then, the definition of a rational exponent can be used.
sqrt(a/b)=sqrt(a)/sqrt(b)
sqrt(a^m)=a^(mn)
p/q= n
It has been proven that ( ab)^n= a^nb^n for rational n.
If a power with base a and rational exponent m is raised to the power of n, where n is rational, then the result is a power with base a and exponent m* n.
Recall that a^(mn) can be defined either as sqrt(a^m) or (sqrt(a))^m. Using the second definition, the last obtained expression can be rewritten. (sqrt(a^p))^(qr) = (sqrt(sqrt(a^p)))^q The root of a root can be expressed using only one root whose index is the product of the original indices. (sqrt(sqrt(a^p)))^q ⇔ (sqrt(a^p))^q Note that since r is an integer number, then r* r is also integer. Using the fact that sqrt(a^m) and (sqrt(a))^m represent the same expression a^(mn), the power q can be moved inside the radical. (sqrt(a^p))^q ⇔ sqrt((a^p)^q) As p and q are integer numbers, the Power of a Power Property can be used.
(a^m)^n=a^(m* n)
sqrt(a^m)=a^(mn)
Write as a product of fractions
p/r= m, q/r= n
It has been proven that (a^m)^n=a^(m* n) for rational numbers m and n.
Classmates Vincenzo and Magdalena have each simplified the same numeric expression 3^(14)* 3^(12). Yet, they obtained different results.
Magdalena's answer is correct. To see if Vincenzo's answer is correct, rewrite the obtained expression as a radical.
a^(mn)=sqrt(a^m)
Vincenzo's answer is also correct! Therefore, both Magdalena and Vincenzo are correct.
Dylan was asked to simplify the expression x^(12) y^(27) * x^(13) y^(37) and write the answer using rational exponents for a homework assignment. However, Dylan did not pay attention during the lesson and now he has no clue how to find the answer. Use the Product of Powers Property for Rational Exponents and find the answer to help Dylan with his homework!
Commutative Property of Multiplication
a^m*a^n=a^(m+n)
a/b=a * 3/b * 3
a/b=a * 2/b * 2
Add fractions
Multiply
Vincenzo and Magdalena continue with their homework, and this time, they are asked to simplify the numeric expression 2^(56)÷ 2^(15). Once again, they obtained different results!
a÷ b=a/b
a^m/a^n= a^(m-n)
a/b=a * 5/b * 5
a/b=a * 6/b * 6
Subtract fractions
Since Vincenzo's answer is 2^(16), he is not correct. To see if Magdalena is correct, the obtained expression needs to be rewritten as a radical.
a^(mn)=sqrt(a^m)
Since Magdalena wrote sqrt(2^5), she is not correct. Therefore, neither Vincenzo nor Magdalena obtained the correct answer this time.
Dylan is making progress with his homework. In one of the exercises, he is asked to simplify the given expression. 2^(23)x^(12)* 2^(311)/2^(1011)x^(29) Help Dylan to complete the given task and then write the answer using rational exponents.
Commutative Property of Multiplication
a^m*a^n=a^(m+n)
a/b=a * 11/b * 11
a/b=a * 3/b * 3
Add fractions
Write as a product of fractions
a^m/a^n= a^(m-n)
a/b=a * 3/b * 3
a/b=a * 9/b * 9
a/b=a * 2/b * 2
Subtract fractions
Multiply
Dylan is trying to finish the last few exercises of his homework. Help him get a passing grade by matching the equivalent expressions!
Consider the first expression. x^(12)y^(34)/x^(13) Here, the Quotient of Powers Property for Rational Exponents can be used.
a* b/c=a/c* b
a^m/a^n= a^(m-n)
a/b=a * 3/b * 3
a/b=a * 2/b * 2
Subtract fractions
Consider now the second expression. sqrt(x) * x^(15) Here, the radical expression can be written as a power with a rational exponent. Then, the Product of Powers Property for Rational Exponents can be applied.
sqrt(a)=a^(12)
a^m*a^n=a^(m+n)
Now, consider the third expression. sqrt(2)x* 2y/2^(32) Here, the definition of a rational exponent will be used again to rewrite the radical expression. Then, the Product of Powers Property for Rational Exponents and the Quotient of Powers Property for Rational Exponents will be used.
sqrt(a)=a^(12)
Commutative Property of Multiplication
a=a^1
a^m*a^n=a^(m+n)
a* b/c=a/c* b
Finally, consider the last expression. 2x^(13)sqrt(y)/sqrt(2)y^(14)2^(12) Similarly to the previous expression, this one can be simplified by using the definition of a rational exponent and different properties of rational exponents.
Commutative Property of Multiplication
a^m*a^n=a^(m+n)
Add fractions
Write as a product of fractions
a* b/c=a/c* b
a^1=a
a/a=1
Identity Property of Multiplication
Use the Power of a Power Property for Rational Exponents to calculate the exponent after simplifying the given expression. Please enter only the exponent into the answer box and write it as a fraction. Even if it is possible, do not simplify the fraction.
Below are the formulas for the surface area and the volume of a sphere with radius r.
sqrt(a)=a^(12)
(a/b)^m=a^m/b^m
(a b)^m=a^m b^m
a^(12)=sqrt(a)
Calculate root
Rearrange equation
Note that when solving the equation, the principal root was taken. This is because the radius r must be a positive value.
r= SA^(12)/2π^(12)
(a/b)^m=a^m/b^m
(a b)^m=a^m b^m
Calculate power
(a^m)^n=a^(m* n)
1/b* a = a/b
Multiply fractions
a/b=.a /4./.b /4.
Commutative Property of Multiplication
Write as a product of fractions
a=a^1
a^m/a^n= a^(m-n)
a^(- m)=1/a^m
Multiply fractions
In this lesson, the understanding of the properties of exponents was extended to include rational exponents. Using these properties, the challenge presented at the beginning of the lesson can now be solved. sqrt(8x^3) * (x^(12)y)^5/sqrt(2x^2y)* x^(13) Simplify the expression and write the answer using only rational exponents.
sqrt(a)=a^(12)
sqrt(a)=a^(1n)
Now, the properties studied in this lesson can be used to simplify the expression.
(a b)^m=a^m b^m
Rewrite 8 as 2^3
(a^m)^n=a^(m* n)
a* 1/b= a/b
1/b* a = a/b
Commutative Property of Multiplication
a^m*a^n=a^(m+n)
Write as a product of fractions
a^m/a^n= a^(m-n)
Subtract terms
a/b=a * 3/b * 3
a/b=a * 2/b * 2
a = 3* a/3
Subtract fractions
Calculate the value of the numeric expression without using a calculator. Write the answer in exact form. sqrt(25)*sqrt(25)*sqrt(25)/sqrt(25)+sqrt(25)+sqrt(25)
We cannot calculate sqrt(25) without a calculator and we cannot reduce the fraction in its current form. However, we have an addition of three sqrt(25)-terms in the denominator. Therefore, we can start by rewriting this sum as a product.
Now, note that sqrt(25) is a factor of both the numerator and denominator. This means that we can cancel out common factors.
Let's now rewrite the radicals in the numerator as powers with rational exponents.
Next, we can use the Product of Powers Property for Rational Exponents. This property states that if we have a product of two powers with rational exponents and the same base, we can add the exponents and leave the base unchanged.
Finally, we can express the only power with a rational exponent as a radical expression, and evaluate.
The exact answer is 53.
We will start by using the Product of Powers Property for Rational Exponents. This property states that if we have a product of two powers with the same base, we can add the exponents and leave the base unchanged. Then, we will express 9^(12) as a radical and evaluate this expression. Finally, we will add and subtract the terms. Let's do it!
We found that the given numeric expression is equal to 3.
Like in Part A, we will start by using the Product of Powers Property for Rational Exponents. Then, we will express 8^(13) as a radical and evaluate this radical expression. Finally, we will add and subtract the terms.
We found that the given expression is equal to 4.
The radius r of a cone's base is given by the following formula. r=(3V/π h)^(12) Here, V and h are the volume and the height of the cone, respectively. Find the radius of a cone with a volume of 7 cubic centimeters and a height of 5 centimeters. Use π≈ 3.14 and approximate the answer to the nearest centimeter.
Let's start by drawing a cone with a volume of 7 cubic centimeters and a height of 5 centimeters.
Now we can substitute V=7 and h=5 into the given formula for the radius. Because π is a non-terminating and non-repeating decimal number, we will use 3.14 to approximate it.
Next, we will evaluate the obtained expression. To do so, we start by calculating the products in the numerator and the denominator.
Finally, we will use the Power of a Quotient Property for Rational Exponents. This property allows us to have the quotient of two powers instead of the power of a quotient.
We can now rewrite the powers with rational exponents as radical expressions and evaluate. Let's do it!
Rounded to the nearest centimeter, the radius of the base of the cone is 1 centimeter.