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If F (X) is Continuous on [–4, 2] Defined as - Mathematics and Statistics

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Question

If f (x) is continuous on [–4, 2] defined as 

f (x) = 6b – 3ax, for -4 ≤ x < –2
       = 4x + 1,    for –2 ≤ x ≤ 2

Show that a + b =`-7/6`

Solution

Since f is continuous on [-4, 2],

f is continuous on x = -2

`lim_(x->-2^-)f(x)=lim_(x->-2^+)f(x)`

`lim_(x->-2^-)6b-3ax=lim_(x->-2^+)4x+1`

`6b-3a(-2)=4(-2)+1`

`6b+6a=-7`

`(a+b)=-7/6`

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2016-2017 (July)

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