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Wrong Answer
Posted:
Apr 26, 2013 11:08 PM


Hello,
I've discovered that Solve[] gives me the wrong answer for some polynomial equations. For example, consider the following equation, which should have exactly one positive, real answer for t.
p:=(px + t vx)^4 + (py + t vy)^4==1 r:={px>0.5,py>0.5,vx>0.5,vy>0.5} NSolve[p/.r,t]
NSolve gives the right answers if I substitute for px,py,vx and vy before solving. On the other hand, if I use Solve[] this way:
Solve[p,t]/.r
I get a different answer, and it's not correct. Does Solve[] just malfunction with quartic polynomials or is there something else happening?
Chris
mathematica 5.2
Solve[p]



