Asked by simran
solve by quadratics formula 10x^2-1/x=3send answer fast
Answers
Answered by
Reiny
the way you typed it, it is not a quadratic but a cubic
e.g.
10x^2 - 1/x = 3
times x,
10x^3 - 1 = 3x
10x^3 - 3x - 1 = 0 , which is a cubic equation
appr x = .67023
if you meant:
(10x^2 - 1)/x = 3
then
10x^2 - 1 = 3x
10x^2 - 3x - 1 = 0
(2x - 1)(5x + 1) = 0
x = 1/2 or x = -1/5
notice how critical and essential those brackets are in the typing of the problem?
e.g.
10x^2 - 1/x = 3
times x,
10x^3 - 1 = 3x
10x^3 - 3x - 1 = 0 , which is a cubic equation
appr x = .67023
if you meant:
(10x^2 - 1)/x = 3
then
10x^2 - 1 = 3x
10x^2 - 3x - 1 = 0
(2x - 1)(5x + 1) = 0
x = 1/2 or x = -1/5
notice how critical and essential those brackets are in the typing of the problem?