Questions tagged [inequalities]
Questions about handling with inequalities with, e.g., Reduce, Solve, FindInstance etc., their application in defining Regions, and ways to incorporate them into other computations, e.g. integration.
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Why is there a difference in computational speed when judging the size of inequalities in these two forms? [closed]
Method One:
Reduce[ForAll[{x, y, z}, {x > y > 1 > z > 0, a == (1 + x z)/z,
b == (1 + x y)/x, c == (1 + y z)/y}, a > b && c < a]]
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How to perform linear programming in Mathematica based on the following conditions？
How to perform linear programming in Mathematica based on the following conditions, to draw the feasible region defined by -1 <= a + b <= 1 and 1 <= a - b <= 3, and find the range of t==3 ...
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Why does FindInstance[x>0,x] give 27? [closed]
Why does FindInstance[x>0,x] give 27? I would think it would give 1… maybe 2 or some small positive decimal.
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Verifying set emptiness with FindInstance versus Reduce [closed]
I have a semialgebraic set in $\mathbb{R}^4$ that I believe to be empty. FindInstance claims that it is empty in less than ten seconds. But Reduce has run for a week without visible progress --- and ...
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Inequality too complex for Mathematica to solve? [closed]
I'm trying to solve some quite complicated inequalities (not a system), one of them for example being
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Unable to solve/reduce geometric Brownian motion inequality
I am trying to solve a few inequalities like the one below for Z:
S * Exp[(mu - sigma^2/2)*T + Sqrt[T]*sigma*Z] > k
Manually,...
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How can I solve this inequation over positive integers?
$$2023^i + 2023^{101-i}(-1)^i < 0, \quad i\in \mathbb N^+$$
My code:
Reduce[2023^x+2023^(101-x)*(-1)^x<0 && x ∈ PositiveIntegers, x]
gives an error ...
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Most efficient way of defining the following sets for every step $n$
For each $n\in\mathbb{N}$, how do we compute sets $A_n$ and $B_n$ below:
Let $A_1=[0,2/3)$. Let $B_1=(2/3,1]$.
If $A_n$ is a union of intervals, then for each interval cut out the
middle $1/2^{n+1}$ ...
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How can I solve this inequality? Can I provide extra information when doing Solve?
I am new to Mathematica so I could really use your help.
I am hoping to figure out the condition that the following function is larger than 0.
I tried to FullSimplify it and to simplify it myself ...
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Simplifying a logical expression with multivariate polynomials
I have several expressions similar to
a (a b + c d) != 0 || b (a b + c d) != 0 || c (a b + c d) != 0 || d (a b + c d) != 0
and I would like to reduce them ...
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How to numerically find complex non-real roots of a function?
Using Mathematica, how can we numerically find only complexes, but not real roots, of a function?
For example, if we have f:C->C, and we have roots like, R1,R2,...,Rn (real roots, without imaginary ...
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Equation different plots
I have this equation to plot.
f[x]*g[x] >= 310
the problem is how should it be converted?
should I write
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Solving simple inequality gets MMA into an infinite loop [closed]
I was solving inequalities and here is a very simplified version of what I am seeing.
When you do the following, all is well.
Reduce[3^n < 250, n, Integers]
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