Prove that is an irrational number

1.	Prove that is an irrational number
Answer» <P>Answer: explanation is given below explanation Let √3+√5 be a RATIONAL number. A rational number can be WRITTEN in the FORM of p/q where p,q are integers. √3+√5 = p/q √3 = p/q-√5 Squaring on both sides, (√3)² = (p/q-√5)² 3 = p²/q²+√5²-2(p/q)(√5) √5×2p/q = p²/q²+5-3 √5 = (p²+2q²)/q² × q/2p √5 = (p²+2q²)/2pq p,q are integers then (p²+2q²)/2pq is a rational number. Then √5 is also a rational number. But this contradicts the fact that √5 is an irrational number. So,our SUPPOSITION is false. Therefore, √3+√5 is an irrational numbe

Answer»

<P>Answer:

explanation is given below

explanation

Let √3+√5 be a RATIONAL number.

A rational number can be WRITTEN in the FORM of p/q where p,q are integers.

√3+√5 = p/q

√3 = p/q-√5

Squaring on both sides,

(√3)² = (p/q-√5)²

3 = p²/q²+√5²-2(p/q)(√5)

√5×2p/q = p²/q²+5-3

√5 = (p²+2q²)/q² × q/2p

√5 = (p²+2q²)/2pq

p,q are integers then (p²+2q²)/2pq is a rational number.

Then √5 is also a rational number.

But this contradicts the fact that √5 is an irrational number.

So,our SUPPOSITION is false.

Therefore, √3+√5 is an irrational numbe

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