caliefleurette Posted January 12, 2014 Report Share Posted January 12, 2014 Consider f(x) = 2kx2 – 4kx + 1, for k ≠ 0. The equation f(x) = 0 has two equal roots. (a) Find the value of k. Anyone know the answer? I'm confused of what to do... i know that b2-4ac=0 but it doesn't help a lot because16k2-8k2=08k2=0and that doesn't work...Thank you Reply Link to post Share on other sites More sharing options...
twilight Posted January 12, 2014 Report Share Posted January 12, 2014 it should be 16k2-8k not 8k2 Reply Link to post Share on other sites More sharing options...
Guest Posted January 12, 2014 Report Share Posted January 12, 2014 (edited) I dont know where you have 16k2-8k2=0 the 8k^2 from (as this is the -4ac part, therefore -4*(2k)*(1) is equal to -8k not -8k^2...Then: 16k2-8k=0. then you can factorize or use the quadratic formula... Then just continue and you should get that k= 0.5. Edited January 12, 2014 by dvirchow Reply Link to post Share on other sites More sharing options...
Fiz Posted January 12, 2014 Report Share Posted January 12, 2014 Here it is. Good luck! Reply Link to post Share on other sites More sharing options...
caliefleurette Posted January 12, 2014 Author Report Share Posted January 12, 2014 Right right right thanks a lot! Reply Link to post Share on other sites More sharing options...
caliefleurette Posted January 12, 2014 Author Report Share Posted January 12, 2014 now here's another one Let f(x) = 3 ln x and g(x) = ln 5x3. (a) Express g(x) in the form f(x) + ln a, where a +.That one is easy (3ln(x)+ln(5))(b) The graph of g is a transformation of the graph of f. Give a full geometric description of this transformation. I'm confused about that one. Should I say the graph moves 5 units to the right and 3 units...?Thanks for the help Reply Link to post Share on other sites More sharing options...
Fiz Posted January 12, 2014 Report Share Posted January 12, 2014 (edited) Since, the graph of f(x) can be transformed to g(x) we need to notice:1- function g(x) has x multiplied by 5, which is a horizontal stretch by a factor of (1/5).2- Both function are multiplied by 3, so there is not translations or stretches on the y-axis Edited January 12, 2014 by Fiz 1 Reply Link to post Share on other sites More sharing options...
caglaber Posted May 3, 2020 Report Share Posted May 3, 2020 On 1/12/2014 at 3:16 PM, Fiz said: Here it is. Good luck! On 1/12/2014 at 3:16 PM, Fiz said: Here it is. Good luck! where did you found this pic? If you know please tell me bec ı really need those answers. Reply Link to post Share on other sites More sharing options...
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