Bi and Trinomials

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Bi and Trinomials

by dtweah » Thu May 28, 2009 2:40 am
For which of the following expressions is it true that the value of the expression is the same for x = 587 as for x = -587 ?

I. 1 - 2x
II. 1 - 2x^2
III. (1 - 2x)2

(A) I only
(B) II only
(C) I and III only
(D) II and III only
(E) I, II, and III
Source: — Problem Solving |

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by sacx » Thu May 28, 2009 4:21 am
if you substitude x = 587 and -587 in all the 3 expressions you will find only II will give you the same value, since when x is squared - it really doesn't matter whether x is negative or positive - the result will always be postive.

B
SACX