Prove that y3 is irrational

1.	Prove that y3 is irrational
Answer» Let us assume that √3 is a rational number. then, as we know a rational number should be in the form of p/q where p and q are co- prime number. So, √3 = p/q { where p and q are co- prime} √3q = p Now, by squaring both the side we get, (√3q)² = p² 3q² = p² ........ ( i ) So, if 3 is the factor of p² then, 3 is also a factor of p ..... ( ii ) => Let p = 3m { where m is any integer } squaring both sides p² = (3m)² p² = 9m² putting the value of p² in equation ( i ) 3q² = p² 3q² = 9m² q² = 3m² So, if 3 is factor of q² then, 3 is also factor of q Since,3 is factor of p & q both So, our assumption that p & q are co- prime is wrong Therefore√3 is an irrational numberLike if you find it useful

Answer»

Let us assume that √3 is a rational number.

then, as we know a rational number should be in the form of p/q

where p and q are co- prime number.

So,

√3 = p/q { where p and q are co- prime}

√3q = p

Now, by squaring both the side

we get,

(√3q)² = p²

3q² = p² ........ ( i )

So,

if 3 is the factor of p²

then, 3 is also a factor of p ..... ( ii )

=> Let p = 3m { where m is any integer }

squaring both sides

p² = (3m)²

p² = 9m²

putting the value of p² in equation ( i )

3q² = p²

3q² = 9m²

q² = 3m²

So,

if 3 is factor of q²

then, 3 is also factor of q

Since,3 is factor of p & q both

So, our assumption that p & q are co- prime is wrong

Therefore√3 is an irrational numberLike if you find it useful

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