posted by Akash on .
Can anybody tell me step wise step how to solve this quadratic equation?
Please tell me step wise step as i haven't solved such type of equations before.
Even you subject is "Quadratic Equations", the problem you submitted is a cubic equation, and there appears to be no typo.
We will solve the cubic as it is posted.
We note that the coefficients add up to zero if we reverse the sign of x^3, i.e. (-1)-3+4=0
This indicates that x=-1 is a zero.
Use long polynomial division to reduce the equation to:
which is a quadratic equation.
We can solve by factorization:
x²-4x+4 = 0
Therefore x=-1 or x=2(multiplicity=2), i.e. x=-1, x=2 or x=2.
any other easy method
I do not see an easier method except factoring trial and error. For this particular problem, you will probably get the answers by trial factoring quite easily.
Remember that this is a cubic equation, which actually has a solution formula more complicated than the above.
There is also the Newton-Ralphson approximation method by iterations.
The above methods (factoring, long division, quadratic equation) do not introduce any algebraic operation that is beyond secondary school level.
N+ ( n+2)=16