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Lim (x → a) [sin(√x) - sin(√a)] / (x - a)

User Amja
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1 Answer

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Final answer:

To find the limit of the given expression, rewrite it in terms of u and v, then use the limit rule for sin(x)/x. The limit is cos(v) / (2 * √a).

Step-by-step explanation:

To find the limit of the given expression, we can use the fact that the limit of sin(x)/x as x approaches 0 is 1. We can rewrite the expression as:

lim (x → a) [sin(√x) - sin(√a)] / (x - a)

= lim (x → a) [(sin(√x) - sin(√a))/(√x - √a)] * [(√x - √a)/(x - a)]

By substituting u = √x and v = √a, we can rewrite the expression as:

= lim (u → v) [sin(u) - sin(v)] / (u² - v²)

= lim (u → v) [sin(u) - sin(v)] / [(u - v)(u + v)]

= lim (u → v) [(sin(u) - sin(v))/(u - v)] * 1/(u + v)

= cos(v) / (2 * √a)

User Stan Wiechers
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