Question 507081
The domain is all the values that x is allowed to take by the rules of algebra.
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The rules of algebra say that you cannot take the square root of a negative number.
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Therefore the quantity for which you are trying to find a square root must be zero or positive.
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This means that {{{x^2 - 36}}} is allowed to be zero or positive (greater than zero). So we can write:
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{{{x^2 - 36 >= 0}}}
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Add 36 to both sides of this inequality to eliminate the -36 on the left side. The inequality becomes:
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{{{x^2 >= 36}}}
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Take the square root of both sides to find that:
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{{{x >= sqrt(36)}}}
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{{{x >= 6}}}
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Therefore the domain of x is that x is allowed to take the value +6 and any other positive value greater than +6. This is the answer to this problem.
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Hope this helps you to understand this problem better.