SOLUTION: Find the domain of each function. a. h(x)= x+3/x-5 b. SQRT x^2+7

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Question 43466: Find the domain of each function.
a. h(x)= x+3/x-5
b. SQRT x^2+7

Answer by Nate(3500) About Me  (Show Source):
You can put this solution on YOUR website!
a. h(x) = x+3 / x-5
y+=+%28x+%2B+3%29%2F%28x+-+5%29
The denominator can not be equal to five because anything divided by zero is undefined.
Domain: x%3C5 or x%3E5
<====(5)====>
+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+%28x+%2B+3%29%2F%28x+-+5%29+%29+
b. SQRT x^2+7
y+=+sqrt%28x%5E2+%2B+7%29
You can not take the square root of a negative number.
x%5E2+%2B+7+%3E=+0
x%5E2+%3E=+-7
x+%3E=+sqrt%28-7%29 and x+%3E=+-sqrt%28-7%29
x+%3E=+i%2Asqrt%287%29 and x+%3E=+-i%2Asqrt%287%29
Domain: all reals
+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+sqrt%28x%5E2+%2B+7%29+%29+