Algebra lineare Esempi
3x+3y+3z=6 , x−y=−3 , −4x+y−z=−1
Passaggio 1
Scrivi il sistema di equazioni sotto forma di matrice.
⎡⎢⎣33361−10−3−41−1−1⎤⎥⎦
Passaggio 2
Passaggio 2.1
Multiply each element of R1 by 13 to make the entry at 1,1 a 1.
Passaggio 2.1.1
Multiply each element of R1 by 13 to make the entry at 1,1 a 1.
⎡⎢
⎢⎣333333631−10−3−41−1−1⎤⎥
⎥⎦
Passaggio 2.1.2
Semplifica R1.
⎡⎢⎣11121−10−3−41−1−1⎤⎥⎦
⎡⎢⎣11121−10−3−41−1−1⎤⎥⎦
Passaggio 2.2
Perform the row operation R2=R2−R1 to make the entry at 2,1 a 0.
Passaggio 2.2.1
Perform the row operation R2=R2−R1 to make the entry at 2,1 a 0.
⎡⎢⎣11121−1−1−10−1−3−2−41−1−1⎤⎥⎦
Passaggio 2.2.2
Semplifica R2.
⎡⎢⎣11120−2−1−5−41−1−1⎤⎥⎦
⎡⎢⎣11120−2−1−5−41−1−1⎤⎥⎦
Passaggio 2.3
Perform the row operation R3=R3+4R1 to make the entry at 3,1 a 0.
Passaggio 2.3.1
Perform the row operation R3=R3+4R1 to make the entry at 3,1 a 0.
⎡⎢⎣11120−2−1−5−4+4⋅11+4⋅1−1+4⋅1−1+4⋅2⎤⎥⎦
Passaggio 2.3.2
Semplifica R3.
⎡⎢⎣11120−2−1−50537⎤⎥⎦
⎡⎢⎣11120−2−1−50537⎤⎥⎦
Passaggio 2.4
Multiply each element of R2 by −12 to make the entry at 2,2 a 1.
Passaggio 2.4.1
Multiply each element of R2 by −12 to make the entry at 2,2 a 1.
⎡⎢
⎢⎣1112−12⋅0−12⋅−2−12⋅−1−12⋅−50537⎤⎥
⎥⎦
Passaggio 2.4.2
Semplifica R2.
⎡⎢
⎢⎣11120112520537⎤⎥
⎥⎦
⎡⎢
⎢⎣11120112520537⎤⎥
⎥⎦
Passaggio 2.5
Perform the row operation R3=R3−5R2 to make the entry at 3,2 a 0.
Passaggio 2.5.1
Perform the row operation R3=R3−5R2 to make the entry at 3,2 a 0.
⎡⎢
⎢
⎢⎣11120112520−5⋅05−5⋅13−5(12)7−5(52)⎤⎥
⎥
⎥⎦
Passaggio 2.5.2
Semplifica R3.
⎡⎢
⎢⎣11120112520012−112⎤⎥
⎥⎦
⎡⎢
⎢⎣11120112520012−112⎤⎥
⎥⎦
Passaggio 2.6
Multiply each element of R3 by 2 to make the entry at 3,3 a 1.
Passaggio 2.6.1
Multiply each element of R3 by 2 to make the entry at 3,3 a 1.
⎡⎢
⎢⎣11120112522⋅02⋅02(12)2(−112)⎤⎥
⎥⎦
Passaggio 2.6.2
Semplifica R3.
⎡⎢
⎢⎣1112011252001−11⎤⎥
⎥⎦
⎡⎢
⎢⎣1112011252001−11⎤⎥
⎥⎦
Passaggio 2.7
Perform the row operation R2=R2−12R3 to make the entry at 2,3 a 0.
Passaggio 2.7.1
Perform the row operation R2=R2−12R3 to make the entry at 2,3 a 0.
⎡⎢
⎢⎣11120−12⋅01−12⋅012−12⋅152−12⋅−11001−11⎤⎥
⎥⎦
Passaggio 2.7.2
Semplifica R2.
⎡⎢⎣11120108001−11⎤⎥⎦
⎡⎢⎣11120108001−11⎤⎥⎦
Passaggio 2.8
Perform the row operation R1=R1−R3 to make the entry at 1,3 a 0.
Passaggio 2.8.1
Perform the row operation R1=R1−R3 to make the entry at 1,3 a 0.
⎡⎢⎣1−01−01−12+110108001−11⎤⎥⎦
Passaggio 2.8.2
Semplifica R1.
⎡⎢⎣110130108001−11⎤⎥⎦
⎡⎢⎣110130108001−11⎤⎥⎦
Passaggio 2.9
Perform the row operation R1=R1−R2 to make the entry at 1,2 a 0.
Passaggio 2.9.1
Perform the row operation R1=R1−R2 to make the entry at 1,2 a 0.
⎡⎢⎣1−01−10−013−80108001−11⎤⎥⎦
Passaggio 2.9.2
Semplifica R1.
⎡⎢⎣10050108001−11⎤⎥⎦
⎡⎢⎣10050108001−11⎤⎥⎦
⎡⎢⎣10050108001−11⎤⎥⎦
Passaggio 3
Utilizza la matrice risultante per determinare le soluzioni finali del sistema di equazioni.
x=5
y=8
z=−11
Passaggio 4
La soluzione è l'insieme delle coppie ordinate che rendono il sistema vero.
(5,8,−11)
Passaggio 5
Scomponi un vettore soluzione riorganizzando ogni equazione rappresentata a scala ridotta per righe della matrice aumentata, risolvendo per la variabile dipendente in ogni riga che dà l'uguaglianza del vettore.
X=⎡⎢⎣xyz⎤⎥⎦=⎡⎢⎣58−11⎤⎥⎦