Posted by HM on .
Another question which is confusing.
The position of an object moving in a straight line is give by s=2t^23t, where is s in metres and t is the time in seconds the object has been in motion..
how long will it is take the object to move 6 meters?
I first used the simplfying rule but it did not work.. Then I used the vertex formula and I got a 2.5 from which I got a negative number..
Moreover then I used the quadratic formula and I got a 2.6 which I put in the formula of 2t^23t and I got a 5.7
Where am I going wrong?
The true answer is 2.6 seconds.

College Math 
bobpursley,
s=2t^23t
2t^23t6=0
t= (3+sqrt(9+48))/4=3/4 +(sqrt57)/4
in my head t= .75+7.5/4=.75+about 1.8
= about 2.6seconds So recheck your quadratic formula solution 
College Math 
HM,
Aha, how silly of me!
My answer were absolutely correct, which was 2.6.. I don't know what urged me to go ahead and put it in the formula again..
Thank you for reconfirming my stupidity.