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Evaluate the following limits : Lim(x t...

Evaluate the following limits :
`Lim_(x to a) (xsqrt(x)-asqrt(a))/(x-a)`

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To evaluate the limit \[ \lim_{x \to a} \frac{x\sqrt{x} - a\sqrt{a}}{x - a}, \] we can follow these steps: ### Step 1: Rewrite the expression We start with the limit: \[ \lim_{x \to a} \frac{x\sqrt{x} - a\sqrt{a}}{x - a}. \] ### Step 2: Substitute \( x = a + h \) Let \( h = x - a \). As \( x \to a \), \( h \to 0 \). Thus, we can rewrite the limit as: \[ \lim_{h \to 0} \frac{(a + h)\sqrt{a + h} - a\sqrt{a}}{h}. \] ### Step 3: Expand \( \sqrt{a + h} \) using Taylor series Using the binomial expansion for small \( h \): \[ \sqrt{a + h} \approx \sqrt{a} + \frac{1}{2\sqrt{a}}h. \] Substituting this back into our limit gives: \[ \lim_{h \to 0} \frac{(a + h)\left(\sqrt{a} + \frac{1}{2\sqrt{a}}h\right) - a\sqrt{a}}{h}. \] ### Step 4: Simplify the expression Expanding the numerator: \[ = \lim_{h \to 0} \frac{a\sqrt{a} + h\sqrt{a} + \frac{1}{2\sqrt{a}}ah + \frac{1}{2\sqrt{a}}h^2 - a\sqrt{a}}{h}. \] This simplifies to: \[ = \lim_{h \to 0} \frac{h\sqrt{a} + \frac{1}{2\sqrt{a}}ah + \frac{1}{2\sqrt{a}}h^2}{h}. \] ### Step 5: Factor out \( h \) Factoring \( h \) out of the numerator: \[ = \lim_{h \to 0} \left(\sqrt{a} + \frac{1}{2\sqrt{a}}a + \frac{1}{2\sqrt{a}}h\right). \] ### Step 6: Evaluate the limit As \( h \to 0 \): \[ = \sqrt{a} + \frac{1}{2\sqrt{a}}a = \sqrt{a} + \frac{a}{2\sqrt{a}} = \sqrt{a} + \frac{1}{2}\sqrt{a} = \frac{3}{2}\sqrt{a}. \] Thus, the limit evaluates to: \[ \frac{3}{2}\sqrt{a}. \] ### Final Answer \[ \lim_{x \to a} \frac{x\sqrt{x} - a\sqrt{a}}{x - a} = \frac{3}{2}\sqrt{a}. \]
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