Suppose that the function \( f \) is defined, for all real numbers, as follows. \[ f(x)=\left\{\begin{array}{cc}-2 x+3 & \text { if } x<2 \\ x-3 & \text { if } x \geq 2\end{array}\right. \] Graph the function \( f \). Then determine whether or not the function is continuous
Real Tutor Solution
Answer
Solution
Reviewed and approved by the UpStudy tutoring team
Beyond the Answer
To graph the piecewise function \( f(x) \), we’ll break it down into two parts based on the defined intervals: 1. For \( x < 2 \), the function is given by \( f(x) = -2x + 3 \). This is a line with a slope of -2 that intersects the y-axis at (0, 3). For \( x < 2 \), you can plot points like \( f(0) = 3 \), \( f(1) = 1 \), and \( f(2) \) (though it won't be included in this part of the graph). 2. For \( x \geq 2 \), the function is defined as \( f(x) = x - 3 \). This is another line with a slope of 1 that intersects the y-axis at (0, -3). You can plot points like \( f(2) = -1 \), \( f(3) = 0 \), and so on. When you put these two parts together, you will see that the graph consists of two linear pieces: one decreasing line segment for \( x < 2 \) and another increasing line segment starting from \( x = 2 \). To check for continuity, we need to see if the function is continuous at the point where the definitions change, \( x = 2 \): 1. Evaluate \( f(2) = 2 - 3 = -1 \). 2. Check the limit from the left as \( x \) approaches 2: \( \lim_{x \to 2^-} f(x) = -2(2) + 3 = -1 \). 3. Check the limit from the right as \( x \) approaches 2: \( \lim_{x \to 2^+} f(x) = 2 - 3 = -1 \). Since the left limit, right limit, and the function value at \( x = 2 \) are all equal to -1, \( f(x) \) is continuous everywhere, including at \( x = 2 \). Therefore, the function is continuous.