Adding a quadratic term flips the signs of the coefficients
6463
Coefficient changes sign when adding a variable in logistic regression
126261
Extraneous solution from substituting in equations
110297
Problem related to quadratic equations
117099
Coefficient Problem (polynomial expansion)
8970
Proving the cross product matrix tranformation identity with an alternative solution
127976
What does upside down "v" ($\wedge$) mean in this equation?
132931
Determining the parity of the coefficients of a quadratic given that there is a rational solution
81757
How to include a linear and quadratic term when also including interaction with those variables?
148069
Different Sum signs
109864
What does it mean to have a lone plus sign in the exponent/superscript (Modified Weiszfeld algorithm)
52078
Multinomial Coefficients Definition in expansion of $(1+x+x^2+\cdots+x^l)^n$
131941
Solve quadratic congruences.
6984
Inverting $a+b\sqrt{2}$ in the field $\Bbb Q(\sqrt{2})$
94552
Is it possible in R (or in general) to force regression coefficients to be a certain sign?
32122
Find the coefficient of the term $x^2$ in $\left(x+\frac 2x\right)^{4}$
57744
Strange behaviour of binomial coefficient's delimiters
84228
What's the best way make an "augmented" coefficient matrix?