N spire cas cx and ti-89 can't evaluate improper integral

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Let X have an exponential distribution with parameter λ. a. Determine E[X] and E[X^2] using partial integration.

Okay so I thought I could just plug that in my ti-89 or nspire cas cx, but neither can do it.

E[X] = $$\int_0^∞ xλe^{-λx} \,dx,$$ However that just gives me undef for both calculators. Wolfram alpha is happy to do it.

https://www.wolframalpha.com/input/?i=integral(xae%5E(-a*x))+from+0+to+infinity

Is there a way to do this on these calculators?