Subjects calculus

Continuity Piecewise 098762

Step-by-step solutions with LaTeX - clean, fast, and student-friendly.

Use the AI math solver

1. **Problem Statement:** We have a piecewise function \( j(x) \) defined as: $$ j(x) = \begin{cases} f(x) & \text{if } -5 \leq x < 0 \\ g(x) & \text{if } 0 \leq x \leq 1 \\ h(x) = x \ln(x) + k & \text{if } x > 1 \end{cases} $$ We need to analyze continuity at \( x = -4, -2, 0 \), find \( k \) for continuity at \( x=1 \), find horizontal asymptotes of \( f(x) \), and find \( \lim_{x \to \infty} j(x) \). --- 2. **(a) Continuity at \( x = a \):** Recall the definition of continuity at \( x = a \): $$ \lim_{x \to a} j(x) = j(a) $$ This means the left-hand limit (LHL), right-hand limit (RHL), and function value at \( a \) must all be equal. - **At \( a = -4 \):** - Since \( -5 \leq x < 0 \), \( j(x) = f(x) \) on both sides near \( -4 \). - The graph shows a filled point at \( (-4, 2) \) and an open circle at \( (-4, 0) \) on the y-axis. - The function value \( j(-4) = f(-4) = 2 \) (filled point). - The limit from both sides is \( 2 \) because the function is defined by \( f(x) \) on both sides. - Therefore, \( j(x) \) is continuous at \( x = -4 \). - **At \( a = -2 \):** - \( j(x) = f(x) \) for \( x < 0 \), so near \( -2 \), \( j(x) = f(x) \). - The graph shows no discontinuity or open circles near \( -2 \). - Hence, \( j(x) \) is continuous at \( x = -2 \). - **At \( a = 0 \):** - Left side limit: \( \lim_{x \to 0^-} j(x) = \lim_{x \to 0^-} f(x) \). - Right side limit: \( \lim_{x \to 0^+} j(x) = \lim_{x \to 0^+} g(x) \). - From the graph, \( f(0) \) has an open circle at \( y=2 \), so \( f(0) \) is not defined or not equal to 2. - \( g(0) = 2 \) (filled point). - Since \( \lim_{x \to 0^-} f(x) \neq g(0) \), \( j(x) \) is not continuous at \( x=0 \). --- 3. **(b) Continuity at \( x = 1 \):** We want: $$ \lim_{x \to 1^-} j(x) = j(1) = \lim_{x \to 1^+} j(x) $$ - Left limit: \( \lim_{x \to 1^-} j(x) = \lim_{x \to 1^-} g(x) = g(1) = 1 \) (from table). - Right limit: \( \lim_{x \to 1^+} j(x) = \lim_{x \to 1^+} h(x) = \lim_{x \to 1^+} (x \ln x + k) = 1 \cdot \ln 1 + k = 0 + k = k \). - Function value at 1 is \( j(1) = g(1) = 1 \). Set left and right limits equal: $$ 1 = k $$ So, \( k = 1 \). --- 4. **(c) Horizontal asymptotes of \( f(x) \):** From the graph description: - As \( x \to -5 \), \( f(x) \) approaches \( y = 0 \) (open circle at approx 0). - As \( x \to 0^- \), \( f(x) \) approaches \( y = 2 \) (open circle at 2). Therefore, horizontal asymptotes are: $$ y = 0 \quad \text{and} \quad y = 2 $$ --- 5. **(d) \( \lim_{x \to \infty} j(x) \):** For \( x > 1 \), \( j(x) = h(x) = x \ln x + k \). As \( x \to \infty \), \( \ln x \to \infty \) but grows slower than \( x \), so: $$ \lim_{x \to \infty} x \ln x = \infty $$ Thus, $$ \lim_{x \to \infty} j(x) = \infty $$ Interpretation: The function \( j(x) \) grows without bound as \( x \) becomes very large. --- **Final answers:** - (a) Continuous at \( x = -4 \) and \( x = -2 \), not continuous at \( x = 0 \). - (b) \( k = 1 \) for continuity at \( x = 1 \). - (c) Horizontal asymptotes of \( f(x) \) are \( y = 0 \) and \( y = 2 \). - (d) \( \lim_{x \to \infty} j(x) = \infty \).