okay, so i need to find:

A) for which values of x is x^2 + x + 1 >= (x-1)/(2x-1)

and another similar one

for which values of x is -3x^2 +4x > 1?

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- Aug 29th 2007, 07:44 PMmistykzinequality/proof type thing
okay, so i need to find:

A) for which values of x is x^2 + x + 1 >= (x-1)/(2x-1)

and another similar one

for which values of x is -3x^2 +4x > 1? - Aug 29th 2007, 09:00 PMJameson
- Aug 29th 2007, 09:49 PMearboth
Hello,

for confirmation only I give you the solution of the first one:

#2.

. Now factor the LHS of the inequaltiy:

. You have a product of 2 factors which is positiv. That means both factors must have the same sign. The sign + means that the value is greater than zero, the sign - ...:

. Solve each inequality:

. Collect the results of inequalities which are connected by :

- Aug 29th 2007, 11:31 PMred_dog

Now we make the sign of each factor in a table and we use the rule of signs.

From the last row in the table we have

- Aug 30th 2007, 06:47 AMmistykzthanks
awesome, thanks everyone!