Is 0<y<1? (is y a positive fraction?)
1) 0 < square root of 'y' < 1
=> square root of 'y' is a positive fraction
=>y is a positive fraction (squaring a positive fraction results in a positive fraction)
sufficient
2) y^2=1/4
y=1/2 or y=-1/2
since y can either be a positive or a negative fraction, not sufficient
hence A
Is 0<y<1?
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scoobydooby
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farooq
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scoobydooby wrote:Is 0<y<1? (is y a positive fraction?)
1) 0 < square root of 'y' < 1
=> square root of 'y' is a positive fraction
=>y is a positive fraction (squaring a positive fraction results in a positive fraction)
sufficient
2) y^2=1/4
y=1/2 or y=-1/2
since y can either be a positive or a negative fraction, not sufficient
hence A
You are right.
Why sqr root of 'Y' cannot be -ve as well as +ve?
Does sqrt root of any no. is always +ve?
Regards,
Farooq Farooqui.
London. UK
It is your Attitude, not your Aptitude, that determines your Altitude.
Farooq Farooqui.
London. UK
It is your Attitude, not your Aptitude, that determines your Altitude.
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scoobydooby
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we need to find if y is between 0 and 1
sqr root of 'Y' can be -ve as well as +ve
to get y from the square root, we need to square it, so it becomes positive
say sq. root of y = 1/2 or -1/2
we want y
so y=(1/2 )^2 or (-1/2)^2
both gives y=1/4 (positive)
sqr root of 'Y' can be -ve as well as +ve
to get y from the square root, we need to square it, so it becomes positive
say sq. root of y = 1/2 or -1/2
we want y
so y=(1/2 )^2 or (-1/2)^2
both gives y=1/4 (positive)
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scoobydooby
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farooq,
please refer to the last post in the link, Ian explains square root concept very well
https://www.beatthegmat.com/help-in-nump ... 29290.html
please refer to the last post in the link, Ian explains square root concept very well
https://www.beatthegmat.com/help-in-nump ... 29290.html
