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Find the number of solutions of |x|*3^(...

Find the number of solutions of ` |x|*3^(|x|) = 1`.

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To find the number of solutions for the equation \( |x| \cdot 3^{|x|} = 1 \), we can break it down into two cases based on the definition of the absolute value. ### Step 1: Define the cases based on the absolute value 1. **Case 1**: \( x \geq 0 \) - Here, \( |x| = x \). The equation becomes: \[ x \cdot 3^x = 1 \] 2. **Case 2**: \( x < 0 \) - Here, \( |x| = -x \). The equation becomes: \[ -x \cdot 3^{-x} = 1 \quad \text{or} \quad x \cdot 3^{-x} = -1 \] ### Step 2: Analyze Case 1 For \( x \geq 0 \): - We need to solve \( x \cdot 3^x = 1 \). - Define the function \( f(x) = x \cdot 3^x \). - We can analyze the function \( f(x) \): - As \( x \) approaches 0, \( f(0) = 0 \). - As \( x \) increases, \( f(x) \) increases because both \( x \) and \( 3^x \) are increasing functions. To find the intersection with \( y = 1 \): - We can check values: - \( f(0) = 0 \) - \( f(1) = 1 \cdot 3^1 = 3 \) (which is greater than 1) Since \( f(x) \) is continuous and strictly increasing, there is exactly **one solution** in the interval \( [0, 1] \). ### Step 3: Analyze Case 2 For \( x < 0 \): - We need to solve \( x \cdot 3^{-x} = -1 \). - Define the function \( g(x) = x \cdot 3^{-x} \). - Analyze the function \( g(x) \): - As \( x \) approaches 0 from the left, \( g(x) \) approaches 0. - As \( x \) decreases (becomes more negative), \( g(x) \) also decreases because \( 3^{-x} \) increases rapidly. To find the intersection with \( y = -1 \): - Check values: - As \( x \) approaches -1, \( g(-1) = -1 \cdot 3^{1} = -3 \). - As \( x \) approaches 0 from the left, \( g(x) \) approaches 0. Since \( g(x) \) is continuous and strictly decreasing, there is exactly **one solution** in the interval \( (-\infty, 0) \). ### Step 4: Conclusion - From Case 1, we found **1 solution** for \( x \geq 0 \). - From Case 2, we found **1 solution** for \( x < 0 \). Thus, the total number of solutions to the equation \( |x| \cdot 3^{|x|} = 1 \) is: \[ \text{Total Solutions} = 1 + 1 = 2 \]

To find the number of solutions for the equation \( |x| \cdot 3^{|x|} = 1 \), we can break it down into two cases based on the definition of the absolute value. ### Step 1: Define the cases based on the absolute value 1. **Case 1**: \( x \geq 0 \) - Here, \( |x| = x \). The equation becomes: \[ x \cdot 3^x = 1 \] ...
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