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If L=lim(xto0) (sinx+ae^(x)+be^(-x)+clog...

If `L=lim_(xto0) (sinx+ae^(x)+be^(-x)+clog_(e)(1+x))/(x^(3))` exists finitely, then
The value of L is

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To solve the limit problem given, we start with the expression: \[ L = \lim_{x \to 0} \frac{\sin x + ae^x + be^{-x} + c \log_e(1+x)}{x^3} \] ### Step 1: Expand each term using Taylor series 1. **Sine function**: \[ \sin x = x - \frac{x^3}{6} + O(x^5) \] 2. **Exponential functions**: \[ e^x = 1 + x + \frac{x^2}{2} + \frac{x^3}{6} + O(x^4) \] \[ e^{-x} = 1 - x + \frac{x^2}{2} - \frac{x^3}{6} + O(x^4) \] 3. **Logarithmic function**: \[ \log_e(1+x) = x - \frac{x^2}{2} + \frac{x^3}{3} + O(x^4) \] ### Step 2: Substitute the expansions into the limit expression Substituting these expansions into the limit gives: \[ L = \lim_{x \to 0} \frac{\left(x - \frac{x^3}{6}\right) + a\left(1 + x + \frac{x^2}{2} + \frac{x^3}{6}\right) + b\left(1 - x + \frac{x^2}{2} - \frac{x^3}{6}\right) + c\left(x - \frac{x^2}{2} + \frac{x^3}{3}\right)}{x^3} \] ### Step 3: Combine like terms Combining the constant, linear, quadratic, and cubic terms: - **Constant term**: \[ a + b \] - **Linear term**: \[ 1 + a - b + c \] - **Quadratic term**: \[ \frac{a}{2} + \frac{b}{2} - \frac{c}{2} \] - **Cubic term**: \[ -\frac{1}{6} + \frac{a}{6} - \frac{b}{6} + \frac{c}{3} \] Thus, the expression becomes: \[ L = \lim_{x \to 0} \frac{(a + b) + (1 + a - b + c)x + \left(\frac{a}{2} + \frac{b}{2} - \frac{c}{2}\right)x^2 + \left(-\frac{1}{6} + \frac{a}{6} - \frac{b}{6} + \frac{c}{3}\right)x^3}{x^3} \] ### Step 4: Set coefficients of lower powers of x to zero For the limit \(L\) to exist finitely, the coefficients of \(x^0\), \(x^1\), and \(x^2\) must be zero: 1. **Coefficient of \(x^0\)**: \[ a + b = 0 \quad (1) \] 2. **Coefficient of \(x^1\)**: \[ 1 + a - b + c = 0 \quad (2) \] 3. **Coefficient of \(x^2\)**: \[ \frac{a}{2} + \frac{b}{2} - \frac{c}{2} = 0 \quad (3) \] ### Step 5: Solve the system of equations From equation (1), we have: \[ b = -a \] Substituting \(b = -a\) into equation (2): \[ 1 + a - (-a) + c = 0 \implies 1 + 2a + c = 0 \quad (4) \] Substituting \(b = -a\) into equation (3): \[ \frac{a}{2} - \frac{a}{2} - \frac{c}{2} = 0 \implies -\frac{c}{2} = 0 \implies c = 0 \quad (5) \] Substituting \(c = 0\) into equation (4): \[ 1 + 2a = 0 \implies a = -\frac{1}{2} \] Then substituting \(a\) back into equation (1): \[ b = -(-\frac{1}{2}) = \frac{1}{2} \] ### Step 6: Calculate the limit \(L\) Now substituting \(a\), \(b\), and \(c\) back into the cubic term: \[ L = \frac{-\frac{1}{6} - \frac{(-\frac{1}{2})}{6} - \frac{\frac{1}{2}}{6} + \frac{0}{3}}{1} = \frac{-\frac{1}{6} + \frac{1}{12} - \frac{1}{12}}{1} = \frac{-\frac{1}{6}}{1} = -\frac{1}{3} \] ### Final Result: \[ L = -\frac{1}{3} \]

To solve the limit problem given, we start with the expression: \[ L = \lim_{x \to 0} \frac{\sin x + ae^x + be^{-x} + c \log_e(1+x)}{x^3} \] ### Step 1: Expand each term using Taylor series ...
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