Problem with Solve inside a loop

Questions
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1

Hi, I wonder why

Do[Solve[x^2 + m x ==  .2,x],{m,0, 1, 0.1}]

doesn’t work. I have also tried to do the same thing with

For[m = 0, m<1.01, m = m+0.01, Solve[x^2 + m x == .2 m,x]]

but I have no answer. Of course I can compute the roots since it’s a second order equation but this doesn’t change the problem

2

Dear Cyrille,

the input

Table[Solve[x^2 + m x == 0.2, x], {m, 0, 1, 0.1}]

gives

{{{x -> -0.447214}, {x -> 0.447214}}, 
{{x -> -0.5}, {x -> 0.4}}, 
{{x -> -0.558258}, {x -> 0.358258}}, 
{{x -> -0.621699}, {x -> 0.321699}}, 
{{x -> -0.689898}, {x -> 0.289898}}, 
{{x -> -0.762348}, {x -> 0.262348}},
{{x -> -0.838516}, {x -> 0.238516}}, 
{{x -> -0.917891}, {x -> 0.217891}}, 
{{x -> -1.}, {x -> 0.2}}, 
{{x -> -1.08443}, {x -> 0.184429}}, 
{{x -> -1.17082}, {x -> 0.17082}}}

If you prefer the Do command, this seems to work:

Do[Print[Solve[x^2 + m x == 0.2, x]], {m, 0, 1, 0.1}]

Is that what you want?

Cheers,
Marco