Prove that. 4 - 3√2÷5 is irrational
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Let (4-3√2)/5 be a rational number.
A rational number can be written in the form of p/q.
(4-3√2)/5 = p/q
4-3√2 = 5p/q
3√2 = 4-5p/q
3√2 = (4q-5p)/q
√2 = (4q-5p)/3q
p, q are integers then (4q-5p)/3q is a rational number.
Then √2 is also a rational number.
But this contradicts the fact that √2 is an irrational number.
Hence our supposition is false.
Therefore, (4-3√2)/5 is an irrational number.
Hence proved.
A rational number can be written in the form of p/q.
(4-3√2)/5 = p/q
4-3√2 = 5p/q
3√2 = 4-5p/q
3√2 = (4q-5p)/q
√2 = (4q-5p)/3q
p, q are integers then (4q-5p)/3q is a rational number.
Then √2 is also a rational number.
But this contradicts the fact that √2 is an irrational number.
Hence our supposition is false.
Therefore, (4-3√2)/5 is an irrational number.
Hence proved.
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remember this property that
when we (add, subtract, multiply, divide) a rational no. with an irrational no. we always get an irrational no. and vice versa.
here 4 is a rational no. and 32^1/2is an irrational no. so we are subtracting a rational with an irrational so this will be an irrational no.
now 4-32^1/2 is an irrational no. when it is divided by a rational no. ie. 5
we will get
4-32^1/2/5 is an irrational no.
pls. mark as brainliest
when we (add, subtract, multiply, divide) a rational no. with an irrational no. we always get an irrational no. and vice versa.
here 4 is a rational no. and 32^1/2is an irrational no. so we are subtracting a rational with an irrational so this will be an irrational no.
now 4-32^1/2 is an irrational no. when it is divided by a rational no. ie. 5
we will get
4-32^1/2/5 is an irrational no.
pls. mark as brainliest
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