p.t 7/3 root5 is an irrational no

Question

anonymous · Answer

step by step i need d answer cn any1 plss help me .................. :(

amorfide · Answer

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is this your question?

parthkohli · Answer

I assume that "p.t" means "prove that"?

anonymous · Answer

yaaaaaaaaaa @ParthKohli  and @amorfide

amorfide · Answer

I don't know the proof sorry

anonymous · Answer

ok @ParthKohli cn u do it

anonymous · Answer

@Hero cn u help mee

parthkohli · Answer

Hmm. Assume that your number is rational.$${7 \over 3\sqrt5} = {p \over q} \,\wedge  \gcd (p,q) = 1$$

parthkohli · Answer

$${49 \over45 } = {p^2 \over q^2}$$$$49q^2 =45p^2 $$This doesn't seem like the conventional proof. :(

anonymous · Answer

is it correct

parthkohli · Answer

No, I need to find a contradiction which I am unable to do.

anonymous · Answer

uff will u try 2 doo ma frnddd

anonymous · Answer

7/3sqrt5 = p/q   -> sqrt 5  = 7q/3p and square ->

5=49q^2/9p^2  so p^2/q^2 = 49/45 but no integer squares to 45

parthkohli · Answer

Oh, so that was the contradiction!