Q. Determine whether the function f(x) is continuous at x=5.f(x)={3+x2,18+2x,x≤5x>5f(x) is continuous at x=5f(x) is discontinuous at x=5
Check Function Definition: To determine if the function f(x) is continuous at x=5, we need to check three conditions:1. The function is defined at x=5.2. The limit of f(x) as x approaches 5 exists.3. The limit of f(x) as x approaches 5 is equal to the function value at x=5.
Find Left Limit: First, let's check if the function is defined at x=5. We have two expressions for f(x), one for x≤5 and one for x > 5. Since 5 is included in the domain of the first expression, we can use it to find the value of f(5).f(5)=3+52f(5)=3+25f(5)=28The function is defined at x=5.
Find Right Limit: Next, we need to find the limit of f(x) as x approaches 5 from the left (x→5−). We use the expression for x≤5.x→5−limf(x)=x→5−lim(3+x2)x→5−limf(x)=3+(5−)2x→5−limf(x)=3+25x→5−limf(x)=28
Compare Limits: Now, we need to find the limit of f(x) as x approaches 5 from the right (x→5+). We use the expression for x > 5.limx→5+f(x)=limx→5+(18+2x)limx→5+f(x)=18+2(5+)limx→5+f(x)=18+10limx→5+f(x)=28
Verify Continuity: Since the limit from the left and the limit from the right both exist and are equal, the limit of f(x) as x approaches 5 exists and is equal to 28.
Verify Continuity: Since the limit from the left and the limit from the right both exist and are equal, the limit of f(x) as x approaches 5 exists and is equal to 28.Finally, we compare the limit of f(x) as x approaches 5 to the function value at x=5. Since both are equal to 28, the function is continuous at x=5.
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