prove that 7–2√2 is irrational number.
Answers
Answered by
12
Heya here is your answer:
_____________________________________________________________
If we add, multiply, divide, subtract anything from any irrational number then the whole no. becomes irrational so we just have to prove √2 irrational
_____________________________________________________________
Here is the process:
Let √2 is rational no. a/b where a and b are co-prime
cross multiplying √2 and a/b
a = √2b
Squaring both sides
a² = 2b² ⇒ Equation 1
a²/2 = b²
⇒2 divide a²
⇒2 divide a
Putting a = 2c in equation 1
(2c)² = 2b²
4c² = 2b²
2c² = b²
c² = b²/2
⇒2 divide b²
⇒2 divide b
2 divide both a and b and our assumption was wrong.
So we conclude that √5 is irrational and hence 7-2√2 is irrational
Hence Proved.
Hope it helps!
mark as brainliest!
God bless you! ^_^
_____________________________________________________________
If we add, multiply, divide, subtract anything from any irrational number then the whole no. becomes irrational so we just have to prove √2 irrational
_____________________________________________________________
Here is the process:
Let √2 is rational no. a/b where a and b are co-prime
cross multiplying √2 and a/b
a = √2b
Squaring both sides
a² = 2b² ⇒ Equation 1
a²/2 = b²
⇒2 divide a²
⇒2 divide a
Putting a = 2c in equation 1
(2c)² = 2b²
4c² = 2b²
2c² = b²
c² = b²/2
⇒2 divide b²
⇒2 divide b
2 divide both a and b and our assumption was wrong.
So we conclude that √5 is irrational and hence 7-2√2 is irrational
Hence Proved.
Hope it helps!
mark as brainliest!
God bless you! ^_^
Similar questions