Question

The domain of y = f(x) = _ is(a) R - {0}(b) R(c) (-2,1)(d) (-1.1)​

Answer 1

Answer:

The domain of a function is the set of all possible x values that satisfy the equation. We cannot answer this question without first knowing what the equation for f(x) is.

Step-by-step explanation:

Take for example the function y = f(x) = $x^{2} +3$. Here, you can plug in literally any value for x and still get our a real number. Thus, the domain of f(x) is (-∞, ∞).

However, if your function is y = f(x) = $\frac{2}{\sqrt{x+3} }$ , not every x value is acceptable. First, we cannot have the denominator (bottom part) of the fraction be zero, because division by zero is undefined. Thus, x = -3 is not an acceptable value for x.

We also cannot take the square root of a negative number. Thus, we have the rule that x + 3 must be greater than or equal to zero.

$x+3 > 0\\\\x > -3$

Normally we would use greater than or equal to zero, but because this is in the denominator, we don't want it to equal zero (and thus x = -3 is not acceptable).

So, the domain of x is (-3, ∞). The parenthesis tell us we do not include the negative three and we do not include infinity. In other words, the domain of x is all numbers greater than -3 but less than infinity.

So, first look at your equation for f(x), then see which values of x don't break the rules of math like division by zero or square roots of negative numbers. Good luck!

Answer 2

The correct answer is b