Answer:
A. -4
Step-by-step explanation:
Given the function f(x) = x + 3 for x ≤ -1 and 2x - c for x > -1, for the function to be continuous, the right hand limit of the function must be equal to its left hand limit.
For the left hand limit;
The function at the left hand occurs at x<-1
f-(x) = x+3
f-(-1) = -1+3
f-(-1) = 2
For the right hand limit, the function occurs at x>-1
f+(x) = 2x-c
f+(-1) = 2(-1)-c
f+(-1) = -2-c
For the function f(x) to be continuous on the entire real line at x = -1, then
f-(-1) = f+(-1)
On equating both sides:
2 = -2-c
Add 2 to both sides
2+2 = -2-c+2
4 =-c
Multiply both sides by minus.
-(-c) = -4
c = -4
Hence the value of c so that f(x) is continuous on the entire real line is -4
