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Need help finding two values of a continuous function that make it continuous at 5

Need help finding two values of a continuous function that make it continuous at 5-example-1

1 Answer

4 votes

We have


\displaystyle\lim_(x\to5^-)f(x)=\lim_(x\to5)b-2x=b-10


\displaystyle\lim_(x\to5^+)f(x)=\lim_(x\to5)-(150)/(x-b)=(150)/(b-5)

with
f(5) equal to the limit from the right as
x\to5.

We need to get


b-10=(150)/(b-5)\implies(b-5)(b-10)=150\implies b^2-15b-100=(b-20)(b+5)=0


\implies b=20\text{ or }b=-5

The larger solution in absolute value is
b=20.

User Jeff Morrris
by
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