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Questions › JNU › JNU SIS 2017 › Q32
2 marks, −1Statistics › Random variables and standard distributions › Expectation and varianceModerateabout 2 min

JNU SIS 2017 Question 32: Random variables and standard distributions

If the probability density function of XXX is f(x)=1+αx2f(x) = \dfrac{1 + \alpha x}{2}f(x)=21+αx​; −1≤x≤1-1 \leq x \leq 1−1≤x≤1, −1≤α≤1-1 \leq \alpha \leq 1−1≤α≤1, then the expectation of XXX is

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If the probability density function of X is f(x) = (1 + α x)/2; -1 ≤ x ≤ 1, -1 ≤ α ≤ 1, then the expectation of X is (A) 6/α (B) α/3 (C) α/2 (D) 3/α

Also written as: If the probability density function of X is f(x) = (1 + alpha x)/2; -1 <= x <= 1, -1 <= alpha <= 1, then the expectation of X is

Random variables and standard distributions has come up 173 times in 7 exams since 2005.

What this question tests

This question is on Expectation and variance, part of Random variables and standard distributions in Statistics.

The mean and spread of a random variable, and how they change under transformations and sums.

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Question from the JNU SIS 2017 paper. Solutions are TestStop's own. Not affiliated with or endorsed by any examination authority.