root2+5 rational or irrational?
answer fast i will brainlist you!
Answers
Answered by
27
: Required Answer
Let us assume that √2+√5 is a rational number.
➝ A rational number can be written in the form of p/q where p,q are integers and q≠0
➝ √2+√5 = p/q
➝ On squaring both sides we get,
➝ (√2+√5)² = (p/q)²
➝ √2²+√5²+2(√5)(√2) = p²/q²
➝ 2+5+2√10 = p²/q²
➝ 7+2√10 = p²/q²
➝ 2√10 = p²/q² – 7
➝ √10 = (p²-7q²)/2q
➝ p,q are integers then (p²-7q²)/2q is a rational number.
➝ Then √10 is also a rational number.
➝ But this contradicts the fact that √10 is an irrational number.
Our assumption is incorrect
❍ √2+√5 is an irrational number.
Answered by
4
✓2+5 is irrational number
Hope it's help you
Please mark me brainleast answer
Similar questions