If p is a negative number and 0

Question

If p is a negative number and  0 < s < |p| , which of the following must also be a negative number?

A)  (p+s)^2

B)  (p-s)^2

C)  (s-p)^2

D)  p^2-s^2

E)  s^2-p^2

DavidTutorexamPAL · Answer

As all we're given are variables, we'll pick simple numbers to eliminate incorrect answers.
This is an Alternative approach.

Let's start with s = 1 and p = -2.
Then
(A) is (-1)^2 = 1. NO
(B) is (-3)^2 = 9. NO
(C) is 3^2 = 9. NO
(D) is (-2)^2 - 1^2 = 4 - 1 = 3. NO
(E) must be our answer. Let's verify: 1^2 - (-2)^2 = 1 - 4 = -3.

(E) is our answer.

SUPMUN · Answer

E;

In the number line value of S will be between 0 and +Mod p,

Therefore P2-s2 will always be negative.

Mikimix · Answer

Faster way:
First three answers are wrong. Elevating to the two the whole sum will lead for sure to a positive number. 
For the least two answers (D and E) we know that both of the numbers ( p and s ) will be positive due to the elevation to the power of two. We know as well that p is greater than s so if we want a negative sum we need to subtract p to s.
The correct answer is E

Working4RTW · Answer

Based on the question we know that S is positive, P is negative, but the absolute value of P is greater than S. This means no matter what S is, P squared will be greater than S squared.

The first three answers we can disregard immediately because they are all a sum or difference of S & P but it is squared. So no matter what actual sum or difference is the result squared will be positive.

Now we are left with only D & E as possible solutions to the problem. D is P^2 - S^2, and because the absolute value of P is greater than S, we know that P^2 will be greater than S^2. Example, if S =2, then P is a negative number that is less than -2. So let's assume it's -3.

-3^2 - 2^2 = 9 - 4 = 5. It's positive, and no matter what we substitute in for P & S, as long as the absolute value of P is greater than S, and as such P squared will always be greater than S squared.

The only option left is E.

Sameer251 · Answer

Given 0<s<|p|

p is farther from the origin than s ; 
hence value of p^2 should be greater than s^2 ;

if you glance through the answer options first, OPTION E s^2-p^2 makes sense logically to be a negative number for any plugged values.

If p is a negative number and 0 < s < |p|, which of the following

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