=
=5*5*3
= =75
1) =x+1-1/x-3=x/x-3
меняем знаки под модулем: (х-1)/(x+3)=1
x-1-1/x+3=x-2/x+3
2) =x2-x+3x=-1+1
x2=-2
x=-1
x=2
x2+x+1=3x-1
x2+x-3x+-1-1
x2-2x=-2
x2-2x+2=0
d=-4=> нет корней
3) = x-x=1+5=6
x+4=x-1
x-x=-1-4=-5
4) =2x+1-2x-2=4
2x-2x=4-1+2=4
2x-1-2x+2=4
2x-2x=4+1-2=3
5) =x2-x-1=0
d=3=> нет корней
Объяснение:
Элементы произведения 1-й пары матриц:
c11 = a11 • b11 + a12 • b21 + a13 • b31 = 2 • 1 + 4 • 4 + 3 • 0 = 2 + 16 + 0 = 18
c12 = a11 • b12 + a12 • b22 + a13 • b32 = 2 • 3 + 4 • (-1) + 3 • 0 = 6 - 4 + 0 = 2
c13 = a11 • b13 + a12 • b23 + a13 • b33 = 2 • 5 + 4 • 0 + 3 • 3 = 10 + 0 + 9 = 19
c14 = a11 • b14 + a12 • b24 + a13 • b34 = 2 • (-4) + 4 • 2 + 3 • 7 = (-8) + 8 + 21 = 21
c21 = a21 • b11 + a22 • b21 + a23 • b31 = 3 • 1 + 0 • 4 + 1 • 0 = 3 + 0 + 0 = 3
c22 = a21 • b12 + a22 • b22 + a23 • b32 = 3 • 3 + 0 • (-1) + 1 • 0 = 9 + 0 + 0 = 9
c23 = a21 • b13 + a22 • b23 + a23 • b33 = 3 • 5 + 0 • 0 + 1 • 3 = 15 + 0 + 3 = 18
c24 = a21 • b14 + a22 • b24 + a23 • b34 = 3 • (-4) + 0 • 2 + 1 • 7 = (-12) + 0 + 7 = -5
c31 = a31 • b11 + a32 • b21 + a33 • b31 = 6 • 1 + 7 • 4 + (-1) • 0 = 6 + 28 + 0 = 34
c32 = a31 • b12 + a32 • b22 + a33 • b32 = 6 • 3 + 7 • (-1) + (-1) • 0 = 18 - 7 + 0 = 11
c33 = a31 • b13 + a32 • b23 + a33 • b33 = 6 • 5 + 7 • 0 + (-1) • 3 = 30 + 0 - 3 = 27
c34 = a31 • b14 + a32 • b24 + a33 • b34 = 6 • (-4) + 7 • 2 + (-1) • 7 = (-24) + 14 - 7 = -17
c41 = a41 • b11 + a42 • b21 + a43 • b31 = 7 • 1 + 5 • 4 + 3 • 0 = 7 + 20 + 0 = 27
c42 = a41 • b12 + a42 • b22 + a43 • b32 = 7 • 3 + 5 • (-1) + 3 • 0 = 21 - 5 + 0 = 16
c43 = a41 • b13 + a42 • b23 + a43 • b33 = 7 • 5 + 5 • 0 + 3 • 3 = 35 + 0 + 9 = 44
c44 = a41 • b14 + a42 • b24 + a43 • b34 = 7 • (-4) + 5 • 2 + 3 • 7 = (-28) + 10 + 21 = 3
Элементы произведения 2-й пары матриц:
c11 = a11 • b11 + a12 • b21 = 1 • 2 + 3 • 1 = 2 + 3 = 5
c12 = a11 • b12 + a12 • b22 = 1 • 1 + 3 • 0 = 1 + 0 = 1
c13 = a11 • b13 + a12 • b23 = 1 • 4 + 3 • 6 = 4 + 18 = 22
c14 = a11 • b14 + a12 • b24 = 1 • 5 + 3 • 4 = 5 + 12 = 17
c21 = a21 • b11 + a22 • b21 = (-1) • 2 + (-4) • 1 = (-2) - 4 = -6
c22 = a21 • b12 + a22 • b22 = (-1) • 1 + (-4) • 0 = (-1) + 0 = -1
c23 = a21 • b13 + a22 • b23 = (-1) • 4 + (-4) • 6 = (-4) - 24 = -28
c24 = a21 • b14 + a22 • b24 = (-1) • 5 + (-4) • 4 = (-5) - 16 = -21
c31 = a31 • b11 + a32 • b21 = 5 • 2 + 0 • 1 = 10 + 0 = 10
c32 = a31 • b12 + a32 • b22 = 5 • 1 + 0 • 0 = 5 + 0 = 5
c33 = a31 • b13 + a32 • b23 = 5 • 4 + 0 • 6 = 20 + 0 = 20
c34 = a31 • b14 + a32 • b24 = 5 • 5 + 0 • 4 = 25 + 0 = 25
c41 = a41 • b11 + a42 • b21 = 4 • 2 + 1 • 1 = 8 + 1 = 9
c42 = a41 • b12 + a42 • b22 = 4 • 1 + 1 • 0 = 4 + 0 = 4
c43 = a41 • b13 + a42 • b23 = 4 • 4 + 1 • 6 = 16 + 6 = 22
c44 = a41 • b14 + a42 • b24 = 4 • 5 + 1 • 4 = 20 + 4 = 24
