Can I have some help? please?...

Question

cicilybailey14 · Answer

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phi · Answer

This question can be tricky.  It can be "dangerous" to solve inequalities the same way as solving equations (i.e. when you divide or multiply by a negative quantity, the relation "flips")

cicilybailey14 · Answer

Is there any other way to do it? thats not so tricky?

phi · Answer

however it is always safe to add or subtract the same quantity from both sides

For example
$$ x^3 \ge x^2 \
x^3 -x^2 \ge 0 $$

Is that true for *any* value of x (any real number) ?
to figure it out, factor x^2 from both terms:
$$ x^2 (x - 1)  \ge 0 $$

now ask:  is x^2 positive or negative?   you should know it's always 0 or bigger
next we ask is (x-1) positive or negative?  I can be either, it depends on x
so x-1 can be negative
 because x^2 is positive and (x-1) can be negative
and plus * minus is minus
the product can be negative.  

negative is not bigger  than 0
so the first choice is not try for *all* values of x

cicilybailey14 · Answer

Okay, I think I get that.