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For Which Value of P and W is P+W a rational number. Tell me how you got that answer

1) P= 1/ square root of 3 and W=1/square root of 6
2)P=1/ square root of 4 and W=1/square root of 9
3)P=1/square root of 6 and W=1/square root of 10
4)P=1/square root of 25 and W=1/square root of 2

User Vekerdyb
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2 Answers

5 votes
300.02 if you use the square root of 72
User Scottphc
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6 votes

Answer:

Option 2 - P=1/ square root of 4 and W=1/square root of 9

Explanation:

To find : For Which Value of P and W is P+W a rational number ?

Solution :

Solving each expression,

1) P= 1/ square root of 3 and W=1/square root of 6

i.e.
P=(1)/(√(3)) and
W=(1)/(√(6))


P+W=(1)/(√(3))+(1)/(√(6))


P+W=(\sqrt2+1)/(√(6))


P+W=0.985598559...

It is an irrational number.

2) P=1/ square root of 4 and W=1/square root of 9

i.e.
P=(1)/(√(4)) and
W=(1)/(√(9))


P+W=(1)/(√(4))+(1)/(√(9))


P+W=(1)/(2)+(1)/(3)


P+W=(5)/(6)


P+W=0.833333.....

It is a rational number as repeating decimal.

3) P=1/square root of 6 and W=1/square root of 10

i.e.
P=(1)/(√(6)) and
W=(1)/(√(10))


P+W=(1)/(√(6))+(1)/(√(10))


P+W=(\sqrt5+\sqrt3)/(√(30))


P+W=0.724476056.....

It is an irrational number.

4) P=1/square root of 25 and W=1/square root of 2

i.e.
P=(1)/(√(25)) and
W=(1)/(√(2))


P+W=(1)/(5)+(1)/(√(2))


P+W=(\sqrt2+5)/(5√(2))


P+W=0.9071067811.....

It is an irrational number.

Therefore, Option 2 is correct.

User MicroPyramid
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