Prove that 5 - √2 is irrational number.
Answers
Answer:-
Let us assume 5-√2 is a rational no.
So , according to the definition of rational no.
5-√2 = a/b where a and b are co-prime and b is not equal to zero.
Now shifting 5 to other side we get
-√2=a/b -5
√2= - a/b+5
√2=(-a+5b)/b
Since a , b and 5 are rational so their addition as well as division would be rational ..
But √2 is irrational and √2 cannot be equal to a rational no.
This contradicts the fact that √ 2 is irrational
This contradiction arises when we 5-√2 as rational
So, 5-√2 is irrational
( We can prove √ 2 is irrational )
Answer:
Step-by-step explanation:
Let us assume that 5–√2 is a rational number and it's simplest form is p/q.
then, p and q are integers having no common factor other than 1 and q ≠ 0.
so,
5–√2 = p/q
√2 = 5–p/q
√2 = (5q–p) / 5
thus, p and q are integers and q ≠ 0.
so, (5q–p) /5 is a rational number.
therefore, √2 is also a rational number.
But, this contradicts the fact that √2 is irrational.
The contradiction arises by assuming 5–√2 is rational.
so, our assumption is wrong.