Advanced Search

edrobina

5 Reputation

One Badge

10 years, 250 days
Contact edrobina

MaplePrimes Activity


These are replies submitted by edrobina

@Preben Alsholm  They're variables....

edrobina 5
October 30 2014
0 0

@Preben Alsholm 

They're variables. It would be probably be easiest to just show you the whole thing.

project_real2.pdf

> 

f1 := x -> 2.5*x;

proc (x) options operator, arrow; 2.5*x end proc

 (1)
> 

D( (1) );

2.5

 (2)
> 

df1 := (2): 'df1';

df1

 (3)
> 

f2 := x -> a*x^3 + b*x^2 + c*x + d;

proc (x) options operator, arrow; a*x^3+b*x^2+c*x+d end proc

 (4)
> 

D( (4) );

proc (x) options operator, arrow; 3*a*x^2+2*b*x+c end proc

 (5)
> 

df2 := (5): 'df2';

df2

 (6)
> 

f3 := x -> e*x^3 + f*x^2 + g*x + h;

proc (x) options operator, arrow; e*x^3+f*x^2+g*x+h end proc

 (7)
> 

D( (7) );

proc (x) options operator, arrow; 3*e*x^2+2*f*x+g end proc

 (8)
> 

df3 := (8): 'df3';

df3

 (9)
> 

f4 := x -> i*x^3 + j*x^2 + k*x + l;

proc (x) options operator, arrow; i*x^3+j*x^2+k*x+l end proc

 (10)
> 

D( (10) );

proc (x) options operator, arrow; 3*i*x^2+2*j*x+k end proc

 (11)
> 

df4 := (11): 'df4';

df4

 (12)
> 

f5 := x -> m*x^3 + n*x^2 + o*x + p;

proc (x) options operator, arrow; m*x^3+n*x^2+o*x+p end proc

 (13)
> 

D( (13) );

proc (x) options operator, arrow; 3*m*x^2+2*n*x+o end proc

 (14)
> 

df5 := (14): 'df5';

df5

 (15)
> 

F := x -> piecewise(x <=20, f1(x), x > 20 and x <120, f2(x), x > 120 and x < 220, f3(x), x > 220 and x < 320, f4(x), x > 320 and x <= 400, f5(x));

proc (x) options operator, arrow; piecewise(x <= 20, f1(x), 20 < x and x < 120, f2(x), 120 < x and x < 220, f3(x), 220 < x and x < 320, f4(x), 320 < x and x <= 400, f5(x)) end proc

 (16)
> 

D( (16) );

proc (x) options operator, arrow; piecewise(x <= 20, 2.5, x < 120, 3*a*x^2+2*(-120.*a-0.1666666667e-1)*x+3.166666667+3600.*a, x = 120, undefined, x < 220, 3*(0.3206081081e-3+4.189189189*a)*x^2+2*(-.1508591091-2170.570571*a)*x+357963.9640*a+21.52258258, x = 220, undefined, x < 320, 3*(-0.6106106106e-4+.7357357357*a)*x^2+2*(0.3081706707e-1-647.4474474*a)*x-2.996571572+189231.2312*a, x = 320, undefined, x < 400, 3*(0.1446749739e-2+1.487465727*a)*x^2+2*(-1.549792177-1611.981003*a)*x+545.3938667+575601.2534*a, x = 400, undefined, 400 < x, 0) end proc

 (17)
> 

dF := (17): 'dF';

dF

 (18)
> 

 

> 

 

> 

eq1 := f1(20) = f2(20);

50.0 = 50.00000000

 (19)
> 

eq2 := f2(120) = f3(120);

400000.*a+133.3333333 = 133.3333338+400000.00*a

 (20)
> 

eq3 := f3(220) = f4(220);

16.2062068-235435.4*a = 16.2062061-235435.44*a

 (21)
> 

eq4 := f4(320) = f5(320);

30.0000001 = 30.00001

 (22)
> 

eq5 := df1(20) = df2(20);

2.5 = 2.500000000

 (23)
> 

eq6 := df2(120) = df3(120);

18000.*a-.833333333 = -.83333333+18000.0000*a

 (24)
> 

eq7 := df3(220) = df4(220);

1.69687187+11183.1829*a = 1.696871873+11183.1832*a

 (25)
> 

eq8 := df4(320) = df5(320);

-2.031606612+882.8828*a = -2.0316066+882.883*a

 (26)
> 

eq9 := f2(80) = 140;

140.0000000 = 140

 (27)
> 

eq10 := f3(180) = 25;

24.9999988-0.1e-1*a = 25

 (28)
> 

eq11 := f4(260) = 65;

65.0000004 = 65

 (29)
> 

eq12 := f5(320) = 30;

30.00001 = 30

 (30)
> 

eq13 := f5(400) = 0;

-421.63219-345475.9*a = 0

 (31)
> 

eq14 := df5(400) = 0;

-0.7e-6 = 0

 (32)
> 

eq15 := f5(325) = 16;

16.00001+.1*a = 16

 (33)
> 

eq16 := f4(300) = 60;

59.9999995-0.1e-1*a = 60

 (34)
> 

values := solve({eq1, eq2, eq3, eq4, eq5, eq6, eq7, eq8, eq9, eq10, eq11, eq12, eq13, eq14, eq15, eq16}, {a, b, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p});

Warning, solving for expressions other than names or functions is not recommended.

  

"values:="

 (35)
> 

assign(values);
> 

plot(F(x), x=0..400, y=-50..250);

 
> 

Emma Drobina



Download project_real2.mw

 

Page 1 of 1