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If the function  is continuous, then what is the value of (a + b)?

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  1. 5
  2. 10
  3. 15
  4. 20

Answer (Detailed Solution Below)

Option 1 : 5
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Detailed Solution

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Concept:

For the function to be continuous:

LHL = RHL = f(x)

Where LHL = f(x - α) and RHL = f(x + α)

Calculation:

Given that f(x) is continuous function

LHL = f(x) = RHL

 f(1 - α) = f(1)

 [a + b(1 - α)] = 5

 [a + b - bα] = 5

a + b = 5

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