If x and y are positive integers, is
root(x+y+1) > 3root(x+1) ?
1. y > 8x + 8
2. x+y > 8x + 8
Standard DS options follow.
Please help understand this.
Inequalities
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Let's start by squaring both sides:
is (x + y + 1) > 9(x + 1) ?
or
is x + y + 1 > 9x + 9 ?
or
is y > 8x + 8 ?
S1 says YES, y IS > 8x + 8.
S2 says MAYBE. y > 7x + 8, but we don't know if y > 8x + 8.
is (x + y + 1) > 9(x + 1) ?
or
is x + y + 1 > 9x + 9 ?
or
is y > 8x + 8 ?
S1 says YES, y IS > 8x + 8.
S2 says MAYBE. y > 7x + 8, but we don't know if y > 8x + 8.