The best approximation for sqrt 55 would be: B) 7 2/5
Consider the ordering
... -2 < -1
Now consider the ordering of their absolute values:
... 1 < 2
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Hopefully, you see that changing the sign reflects the sequence across the origin, so that the ordering is reversed when the signs are changed.
So b=-2 so you plug b in
l(-2)l + (-2)^3.
The absolute value of -2 is just 2 so now it is
2 + (-2)^3.
-2 * -2 is 4 but 4 * -2 is -8. So 2 + (-8) or 2 - 8 which comes to equal (-6) or negative six.
