• Sep 2nd 2009, 01:05 PM
mark
hi can someone please show me how to find the value of x which gives the minimum value of 0 in $(3x^2 - 12x + 5)^2$? i don't know the method you would use to get the answer

thanks, Mark
• Sep 2nd 2009, 01:12 PM
countrygirl
Quote:

Originally Posted by mark
hi can someone please show me how to find the value of x which gives the minimum value of 0 in $(3x^2 - 12x + 5)^2$? i don't know the method you would use to get the answer

thanks, Mark

square 3x then subtract 12x from 3x=
-3x +5 then you square that
and you should get 9x + 25= 0

thats all i got.
• Sep 2nd 2009, 01:18 PM
mark
i'm not sure thats the right answer. the book says $x = 2 \pm \sqrt {\frac{7}{3}}$ would you be able to get it from that? (the 7/3 is meant to be in one big bracket under the root sign but i don't know how to write that out)
• Sep 2nd 2009, 01:46 PM
mr fantastic
Quote:

Originally Posted by mark
hi can someone please show me how to find the value of x which gives the minimum value of 0 in $(3x^2 - 12x + 5)^2$? i don't know the method you would use to get the answer

thanks, Mark

Solve $3x^2 - 12x + 5 = 0$.

A variety of methods are possible, including using the quadratic formula.

Edit: duplicate question: http://www.mathhelpforum.com/math-he...tml#post358224. Thread closed.