NAMA : MUHAMMAD FAQIH
KELAS : LINEAR ALGEBRA B
DOSEN PENGAMPU Prof. Dr. Suhartono, M. Kom
library(matlib)
## Warning: package 'matlib' was built under R version 4.2.2
Membuat sebuah matriks 4x4 dengan isi elemen yang sudah ditentukan pada parameter pertama dari fungsi “matrix()”, dan membuat sebuah vektor dengan isi elemen yang sudah ditentukan pada variabel “b”.
A <- matrix(c(8, -3, 6, 9, 1, 1, 0, 1, 3, -4, 2, 0, -1, 0, 4, -4), 4, 4)
b <- c(1, 1, 5, -2)
Tampilkan Persamaan matriks a dan vektor b
showEqn(A, b)
## 8*x1 + 1*x2 + 3*x3 - 1*x4 = 1
## -3*x1 + 1*x2 - 4*x3 + 0*x4 = 1
## 6*x1 + 0*x2 + 2*x3 + 4*x4 = 5
## 9*x1 + 1*x2 + 0*x3 - 4*x4 = -2
echelon(A, b, verbose=TRUE, fractions=TRUE)
##
## Initial matrix:
## [,1] [,2] [,3] [,4] [,5]
## [1,] 8 1 3 -1 1
## [2,] -3 1 -4 0 1
## [3,] 6 0 2 4 5
## [4,] 9 1 0 -4 -2
##
## row: 1
##
## exchange rows 1 and 4
## [,1] [,2] [,3] [,4] [,5]
## [1,] 9 1 0 -4 -2
## [2,] -3 1 -4 0 1
## [3,] 6 0 2 4 5
## [4,] 8 1 3 -1 1
##
## multiply row 1 by 1/9
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 1/9 0 -4/9 -2/9
## [2,] -3 1 -4 0 1
## [3,] 6 0 2 4 5
## [4,] 8 1 3 -1 1
##
## multiply row 1 by 3 and add to row 2
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 1/9 0 -4/9 -2/9
## [2,] 0 4/3 -4 -4/3 1/3
## [3,] 6 0 2 4 5
## [4,] 8 1 3 -1 1
##
## multiply row 1 by 6 and subtract from row 3
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 1/9 0 -4/9 -2/9
## [2,] 0 4/3 -4 -4/3 1/3
## [3,] 0 -2/3 2 20/3 19/3
## [4,] 8 1 3 -1 1
##
## multiply row 1 by 8 and subtract from row 4
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 1/9 0 -4/9 -2/9
## [2,] 0 4/3 -4 -4/3 1/3
## [3,] 0 -2/3 2 20/3 19/3
## [4,] 0 1/9 3 23/9 25/9
##
## row: 2
##
## multiply row 2 by 3/4
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 1/9 0 -4/9 -2/9
## [2,] 0 1 -3 -1 1/4
## [3,] 0 -2/3 2 20/3 19/3
## [4,] 0 1/9 3 23/9 25/9
##
## multiply row 2 by 1/9 and subtract from row 1
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 0 1/3 -1/3 -1/4
## [2,] 0 1 -3 -1 1/4
## [3,] 0 -2/3 2 20/3 19/3
## [4,] 0 1/9 3 23/9 25/9
##
## multiply row 2 by 2/3 and add to row 3
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 0 1/3 -1/3 -1/4
## [2,] 0 1 -3 -1 1/4
## [3,] 0 0 0 6 13/2
## [4,] 0 1/9 3 23/9 25/9
##
## multiply row 2 by 1/9 and subtract from row 4
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 0 1/3 -1/3 -1/4
## [2,] 0 1 -3 -1 1/4
## [3,] 0 0 0 6 13/2
## [4,] 0 0 10/3 8/3 11/4
##
## row: 3
##
## exchange rows 3 and 4
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 0 1/3 -1/3 -1/4
## [2,] 0 1 -3 -1 1/4
## [3,] 0 0 10/3 8/3 11/4
## [4,] 0 0 0 6 13/2
##
## multiply row 3 by 3/10
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 0 1/3 -1/3 -1/4
## [2,] 0 1 -3 -1 1/4
## [3,] 0 0 1 4/5 33/40
## [4,] 0 0 0 6 13/2
##
## multiply row 3 by 1/3 and subtract from row 1
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 0 0 -3/5 -21/40
## [2,] 0 1 -3 -1 1/4
## [3,] 0 0 1 4/5 33/40
## [4,] 0 0 0 6 13/2
##
## multiply row 3 by 3 and add to row 2
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 0 0 -3/5 -21/40
## [2,] 0 1 0 7/5 109/40
## [3,] 0 0 1 4/5 33/40
## [4,] 0 0 0 6 13/2
##
## row: 4
##
## multiply row 4 by 1/6
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 0 0 -3/5 -21/40
## [2,] 0 1 0 7/5 109/40
## [3,] 0 0 1 4/5 33/40
## [4,] 0 0 0 1 13/12
##
## multiply row 4 by 3/5 and add to row 1
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 0 0 0 1/8
## [2,] 0 1 0 7/5 109/40
## [3,] 0 0 1 4/5 33/40
## [4,] 0 0 0 1 13/12
##
## multiply row 4 by 7/5 and subtract from row 2
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 0 0 0 1/8
## [2,] 0 1 0 0 29/24
## [3,] 0 0 1 4/5 33/40
## [4,] 0 0 0 1 13/12
##
## multiply row 4 by 4/5 and subtract from row 3
## [,1] [,2] [,3] [,4] [,5]
## [1,] 1 0 0 0 1/8
## [2,] 0 1 0 0 29/24
## [3,] 0 0 1 0 -1/24
## [4,] 0 0 0 1 13/12
Transformasi matriks A dan vektor b ke dalam bentuk matriks eselon. Dalam bentuk matriks eselon, setiap baris nol pada matriks A diletakkan di bawah baris yang berisi elemen bukan nol dan setiap elemen nol pada kolom k berada di bawah elemen pada baris k yang memiliki elemen bukan nol.