BlueStreak
New member
- Joined
- May 29, 2019
- Messages
- 16
What is the value of k such that (x-k) is a factor of x3-x2+kx-30?
If \((x-k)\) is a factor of the polynomial \(p(x)\) then it must be true that \(p(k)=0\). The Factor Theorem.What is the value of k such that (x-k) is a factor of x3-x2+kx-30?
I have tried long division, but I'm not entirely sure how to do that if I don't know one of the coefficients.
x^2 + (k-1)*x + k^2
-----------------------------------------
x-k ) x^3 - x^2 + k*x -30
x^3 -k*x^2 . .
---------------- . .
(k-1)*x^2 + k*x .
(k-1)*x^2 - k*(k-1)*x .
----------------------- .
k^2*x -30
k^2*x - k^3
---------------
k^3-30 Remainder
Yes it is! It is also a perfect example of why there has been a radical drop in interest among the 'screen generation' is studying mathematics. I have put out a challenge to traditionalist to show a mathematics textbook teaching how one finds \(\sqrt{13}\) by hand.Much slower than pka's method!