1+1

(Sqrt[2])

(Sqrt[2.])

N[(Sqrt[2]),100]

?N

(Sqrt[3])(3^6)(6/3)

LaplaceTransform
LaplaceTransform

2 3
promena=3

promena

auto5=6;
5auto

(*komentar*)

Solve[a*(x^4)-1==0,x]

Plot[Sin[x],{x,0,5}]

3I

Solve[{x+y==4},{x,y}]

Solve[Sin[x]==0,x]

FindRoot[Sin[x]==0,{x,3}]

DSolve[{x''[t]+x'[t]+2x[t]==(1/t)*(E^t),x[1]==2,x'[1]==3},x[t],t];

∫(E^x)*Cos[x]\[DifferentialD]x

Integrate[(E^x)*Cos[x],{x,2,10}]

N[Pi,100]

Limit[((3n-(n^2)*(((-1))^n))/(n+3)),n->∞]

toto=3x
fel=6
toto je fel

Sin[3.];
3.//Sin;
Sin@3.

NDSolve[(t+1)*x''[t]+6*x'[t]+3*x[t]==(((Sin[3t+1]))^10),x[t],{t,1,10}]

(*2 cviceni 23.2.2015*)

res=DSolve[{y'''[t]-y''[t]+y'[t]-y[t]==Cos[t]*(E^(-3*t))+1,y[0]==2,y'[0]==-4,y''[0]==0.},y[t],t];

a/.a->3

b/.a->3

x/.{x->3,x->2}

y/.{x->3,y->4}

x/.{x->3,x->2}[[2]]

x/.{x->3,y->4,x->2}[[2]]

{1,2,3,{4,5,{1,5},2},10}[[4,3]]

D[y[t],{t,3}]

Plot[Sin[x],{x,-4,4}]

resProGraf=y[t]/.res[[1,1]];

y[t]

Plot[{resProGraf,40*Sin[t]},{t,-4,4},AxesLabel->{"t[s]","I[A]"},PlotStyle->{{Hue[0.2], Thickness[0.1],Dashed},{RGBColor[1,0,1],Thickness[0.01],DotDashed}},PlotLabel->"Muj graf proud napeti",PlotRange->{Automatic,{0,50}}]

MRes1=DSolve[{y''''[t]+11*y''[t]+18*y[t]==Sin[t],y[0]==1,y'[0]==-1,y''[0]==3,y'''[0]==-2},y[t],t];

MRes=y[t]/.MRes1[[1]];

Plot[MRes,{t,0,100},PlotStyle->{ Green,Thick,Dashed},PlotLabel->"Muj graf",AxesLabel->{"t[s]","I[A]"}]

(*treti cv 2.3.2015*)

res=FindRoot[{Log[Abs[x-0.5]]==y,y^2==Log[x]},{{x,5},{y,1}}];
iks=x/.res[[1]];
yps=y/.res[[2]];
Plot[{iks*Sin[yps*t],yps*Sin[iks*t]},{t,0,8},PlotStyle->{{Thick,Dashed,Black},{Thick,Red}},PlotLabel->"Graf sin1 sin2",AxesLabel->{"t [s]","sin1, sin2"},GridLines->Automatic,PlotRange->{Automatic,{-4,4}}]

TreeForm[res]

res=FindRoot[{Log[Abs[x-0.5]]==y,y^2==Log[x]},{{x,5},{y,1}}];
iks=x/.res[[1]];
yps=y/.res[[2]];
Plot[{iks*Sin[yps*t],yps*Sin[iks*t]},{t,0,8},PlotStyle->{{Thick,Dashed,Black},{Thick,Red}},PlotLabel->"Graf sin1 sin2",AxesLabel->{"t [s]","sin1, sin2"},GridLines->Automatic,PlotRange->{Automatic,{-4,4}}]

Manipulate[
b=Round[φ1,0.01];
Plot[{iks*Sin[yps*t+φ1],yps*Sin[iks*t+φ2]},{t,0,8},PlotStyle->{{Thick,Dashed,Black},{Thick,Red}},PlotLabel->"Graf sin ("<>ToString[b]<>") sin2",AxesLabel->{"t [s]","sin1, sin2"},GridLines->Automatic,PlotRange->{Automatic,{-4,4}}],{φ1,0,2Pi},{φ2,0,2Pi}]

"Graf sin ("<>ToString[φ1]<>") sin2"

ClearAll[mojeFunkce]
mojeFunkce[a_,b_,c_]:=Solve[a*(x^2)+b*x+c==0,x]

mojeFunkce[1,2,3]

mojeFunkce[a_,b_,c_]:=Module[{res,x1,x2},
res=Solve[a*(x^2)+b*x+c==0,x];
x1=x/.res[[1]];
x2=x/.res[[2]];
N[{x1,x2},2]
]

ClearAll[a,b,c]
h=mojeFunkce[a,b,c]