Solve1
(* soluzione equazioni algebriche *)
y=5x-10==0;
Solve[y,x] (* soluzione esatta *)
{{x -> 2}}
;[o]
{{x -> 2}}
y1=x^2-5x+6==0;
Solve[y1,x] (* soluzione esatta *)
NSolve[y1,x] (* soluzione approssimata *)
{{x -> 3}, {x -> 2}}
{{x -> 3}, {x -> 2}}
{{x -> 2.000000000000000000}, {x -> 3.000000000000000000}}
;[o]
{{x -> 2.}, {x -> 3.}}
y2=x^2-4x+1==0;
Solve[y2,x] (* soluzione esatta *)
InputForm[Solve[y2,x]]
NSolve[y2,x] (* soluzione approssimata *)
{{x -> (4 + 2*3^(1/2))/2}, {x -> (4 - 2*3^(1/2))/2}}
;[o]
4 + 2 Sqrt[3] 4 - 2 Sqrt[3]
{{x -> -------------}, {x -> -------------}}
2 2
InputForm[{{x -> (4 + 2*3^(1/2))/2}, {x -> (4 - 2*3^(1/2))/2}}]
;[o]
{{x -> (4 + 2*3^(1/2))/2}, {x -> (4 - 2*3^(1/2))/2}}
{{x -> 0.2679491924311227065}, {x -> 3.732050807568877294}}
;[o]
{{x -> 0.2679491924311227065}, {x -> 3.732050807568877294}}
Solve[{3x-4==(10-3x)/2},x] (* soluzione esatta *)
{{x -> 2}}
;[o]
{{x -> 2}}
y3=2 a x^2+3 b x==0;
Solve[y3,x] (* soluzione esatta *)
NSolve[y3,x] (* soluzione approssimata *)
{{x -> (-3*b)/(2*a)}, {x -> 0}}
;[o]
-3 b
{{x -> ----}, {x -> 0}}
2 a
{{x -> (SetAccuracy[0, 29.02381832441451765]*b)/a},
{x -> (-1.500000000000000000*b)/a}}
;[o]
0. b -1.5 b
{{x -> ----}, {x -> ------}}
a a
y4=Solve[7x^2-49x==0,x] (* soluzione esatta *)
InputForm[y4]
{{x -> 7}, {x -> 0}}
;[o]
{{x -> 7}, {x -> 0}}
InputForm[{{x -> 7}, {x -> 0}}]
;[o]
{{x -> 7}, {x -> 0}}
N[NSolve[x^2+2x-7==0,x,],5](* soluzione approssimata*)
(* con 5 cifre *)
Solve[x^2+2x-7==0,x] (* soluzione esatta *)
{{x -> 1.828427124746190098}, {x -> -3.828427124746190097}}
;[o]
{{x -> 1.8284}, {x -> -3.8284}}
{{x -> (-2 + 2^(5/2))/2}, {x -> (-2 - 2^(5/2))/2}}
;[o]
5/2 5/2
-2 + 2 -2 - 2
{{x -> ---------}, {x -> ---------}}
2 2