Computer Sciences > GATE 2026 SET-1 > Calculus
Consider the function f: ℝ → ℝ defined as follows:
f(x) = c1ex − c2 loge(1/x), if x > 0
f(x) = 3, otherwise

where c1, c2 ∈ ℝ.
If f is continuous at x = 0, then c1 + c2 = _________. (answer in integer)

Correct : 3

For f to be continuous at x = 0, the right-hand limit as x → 0+ must equal f(0) = 3.
First simplify the expression for x > 0. Since loge(1/x) = −loge(x), the function becomes f(x) = c1ex + c2loge(x) for x > 0.
Taking the limit as x → 0+:
— c1ex → c1e0 = c1 (finite for any c1)
— c2loge(x) → c2 × (−∞) as x → 0+
For the limit to be finite and equal to 3, the logarithm term must not blow up. The only way to prevent this is to have c2 = 0.
With c2 = 0, the limit becomes simply c1. For continuity this must equal f(0) = 3, so c1 = 3.
Therefore c1 + c2 = 3 + 0 = 3.
Correct answer: 3 ✓

Similar Questions

Consider the functions I. e-x II. x2 - sin x III. √x^3+1 Which of the above functions is/are increasing everywhere in [0, 1] ?
#298 MCQ
Let f(x) be a continuous function from R to R such that f(x) = 1 - f(2-x) Which one of the following options is the CORRECT value of ∫02f(x)dx?
#904 MCQ
Let f(x) = x3 + 15x2 - 33x - 36 be a real-valued function. Which of the following statements is/are TRUE?
#963 MSQ

Related Topics

continuity at zero calculus GATE 2026 GATE CS 2026 Set-1 Q39 f continuous x=0 c1 c2 GATE c1ex c2 log continuity limit GATE engineering mathematics GATE 2026 right hand limit logarithm continuity GATE c1+c2 continuity condition GATE

Unique Visitor Count

Total Unique Visitors

Loading......