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Please can somebody help me with this

Please can somebody help me with this-example-1
User Halena
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1 Answer

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Answer: C) it is a rational number

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If a and b are rational numbers, then so is a/b.

Proof: a/b = (p/q) divided by (r/s) = (p/q)*(s/r) = (ps)/(qr)

Example: 1/2 divided by 3/8 = (1/2)*(8/3) = (1*8)/(2*3) = 8/6 = 4/3

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Squaring a rational number leads to another rational number

Proof: (a/b)^2 = [ (ps)/(qr) ]^2 = ( (ps)^2 )/( (qr)^2 )

which is why (a/b)^2 is rational.

Example: (2/3)^2 = (2^2)/(3^2) = 4/9. We have 2/3 to start off with and it leads to 4/9, both of which are rational numbers.

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In each proof I made a = p/q and b = r/s where p,q,r,s are nonzero integers

User Eric Brotto
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