Help me on this please
2 answers:
Answer:
domain x ≥ 7
range y ≥ 9
The 3rd answer
Step-by-step explanation:
* Lats talk about the domain and the range of the function
- The domain is the all values of x which make the function is defined
- The range is all the values of y got from the defined values of x
- In the square roots or any even roots the value under it must be
greater than or equal to zero ( the even roots for negative values is
undefined)
* Lets solve our problem
∵
- In this function we must chose the values of x which makes
x - 7 zero or positive value
∴ Let x - 7 ≥ 0
- Now solve the inequality
∵ x - 7 ≥ 0 ⇒ add 7 to the both sides
∴ x ≥ 7
- The domain of the function is the values of x
∴ The domain of the function is x ≥ 7
- Lets use the first value of x to find the first value of y
∵ x = 7
∴ f(7) = √(7 - 7) + 9 = √0 + 9 = 9
- The first value of the range is 9
∵ The range is values of y corresponding to the values of x
∴ The range of the function is y ≥ 9
* The domain x ≥ 7
The range y ≥ 9
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Therefore:
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And the seventh root of x to the fifth power is:
Therefore:
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