√3+√5 is rational or irrational
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Answered by
0
Answer:
Irrational
Step-by-step explanation:
√3+√5 is irrational but we take that as a rational
(√3+√5)^2=k^2
3+5=k^2
8=k^2
2√2=k
So we can say that √3+√5is an irrational no
Answered by
3
Hey mate!❤️
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- Key points to know wheter a given number is rational or irrational!
- A number is said to be irrational when it is not expressed in form of P/q where , p & q are integers and q is a non zero number!
- Non terminating , non - repeating decimals are also irrational number but not so it is a rational number!
- Also , when a given (√) number is not a perfect square , It will be an irrational number .
- Here ,
√3 + √5 is not a perfect square , so we can't express it in p/q form .
- Hence ,
√3+√5 is an irrational
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We can also prove it by following steps :
Let the required number be x .
Then ,
x = √3 - √5
Squaring both sides ,
x² = (√3-√5)²
x² = 3+5-2√15
x² = 8-2√15
x² + 8 = 2√15
(x²+8)/2 = √15
So , √15 is an irrational number .
Hence Proved ✔
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