Represent a sequence with a Product sign

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I have 2 sequences I have to represent with a Product symbol (Separately of course).

a) $2*\sqrt{3}*\sqrt{4}^3*\sqrt{5}^4$

b) $\dfrac{1}{n}*\dfrac{3}{n+2}*\dfrac{7}{n+3}$

I am clueless on what I should use as a start and end variable. $$\prod_{i=0}^n i$$

For A I was thinking that it has something to do with 2, since you need 2 in the exponent to remove the square root.

Any suggestions?

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Products are like sums (and similar to integrals) in that the name of the index variable does not matter.

In your first sequence, the terms are $2^1=2^{2/2},3^{1/2},4^{3/2},5^{4/2}$, I cannot obviously detect a pattern. But simpler one can serve as an example, say $2^1,3^{1/2},4^{1/3},5^{1/4}$, etc. It's easy to see the denominator in the exponent is one less than the base, and the base goes from 2 to 5. So you get $$ \prod_{k=2}^5 k^{1/(k-1)} = \prod_{k=1}^4 (k+1)^{1/k} $$

Can you now try both sequences after checking the first one for correctness?