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Just need the answers for these 3 questions please, and how to do them (:

Just need the answers for these 3 questions please, and how to do them (:-example-1
User Murmansk
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2 Answers

7 votes

Answer:

x = 2

Explanation:

The topic here is "fractional exponents."

Review: 2^3 = 8 (this is the cube of 2), and so the inverse function is

8^(1/3) = 2 ("8 raised to the fractional exponent 1/3 is 2"

Question a) 49^(1/2) ("49 to the power 1/2") can be rewritten as

(7^2)^(1/2), which simplifies to 7^(2*1/2) = 7^1 = 7

Caution: this is exponentiation, not division. So 49^(1/2) does not equal 49/2.

Question b) ( )^(1/3) = 4

I would prefer to write this as x^(1/3) = 4 and set the goal of finding the value of the base, x.

Then x^(1/3) = 4 ("x raised to the power 1/3 is 4")

Let's elimiinate the fractional exponent on the left by cubing both sides of the equation:

{x^(1/3)}^3 = 4^3, or, after simplification,

x^1 = 64, or, in simplest form,

x = 64

Question c)

Notice that the base here is 1/100

and that the square root of 1 is 1 and that of 100 is 10.

Therefore, the given

{1/100} is equivalent to {1/10)^2

and so we have:

1 1

(------------)^(1/x) = ------- (we are to find x)

10^2 10

Note that 10 is the square root of 10^2, also the square root of 100.

So let's take the square root of 10^2. We get 10.

Therefore, try x = 2 and see whether the given equation is true:

1 1

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

100 10

The square root of 1 is just 1. The square root of 100 is 10.

Therefore the above equation becomes

1 1

----- = ----- and so x = 2 is correct.

10 10

User Vmb
by
4.5k points
5 votes

Answer:

a) 7

b)64

c)2

Explanation:

look at images

Just need the answers for these 3 questions please, and how to do them (:-example-1
Just need the answers for these 3 questions please, and how to do them (:-example-2
Just need the answers for these 3 questions please, and how to do them (:-example-3
User Rajeev Sharma
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4.6k points