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suppose there are 2 defectives among 5... suppose there are 2 defectives among 5, test one at a time until you find the 2nd defective, find: 1.you need at most 3 tests 2.given the 2nd defective found at 3rd test, find the p that you find the 1st defective at 1st test. Thanks.

Homework help: suppose there are 2 defective among five items, you test one item at a time until you identify the second defective. find: 1. you need at most 3 tests. 2.given the second defective item found at the 3rd test, find the Probability that you found the first defective at the...

Thanks very much.

How to integrate (x^3)(e^2x) ? Thanks.

If f(t)=integral of 1/(1+x^2) from t^2 to 0,then f'(t)=? thanks very much.

thanks!

integrate (e^x)/((3-e^x)^2) thanks very much.

thanks.

how to integrate x/(x^2+4)?