Exercise · ZW-CUMULATIVE-DISTRIBUTION-FUNCTION-003 · ★☆☆ Basic
\(X\) has density \(f(x)=2x\) on \([0,1]\). What is \(F(x)\) for \(0\le x\le 1\)?
Choose one option.
A \(2x^2\) B \(x^2\) C \(2x\) D \(x\)
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Explanation \(F(x)=\int_0^x 2t\,dt=x^2\). Differentiating \(x^2\) returns the density \(2x\).
The cumulative distribution function \(F_X\) of a random variable \(X\) gives, for each real number \(x\), the probability \(P\) that \(X\) takes a value less than or equal to \(x\).
\[F_X(x)=P(X\le x)\]
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