Diketahui A = , B = , X = . Jika AX = B, maka x2+y2−xy=....
0
−20
−12
13
10
Diketahui:
A ===
B ===
X ===
AX === B
Ditanya:
x2+y2−xy=?x^2+y^2-xy=?x2+y2−xy=?
Jawab:
Jika A === dan B ===
Rumus mencari X jika AX === B
X === A-1B
Dengan demikian,
X === 12(−1)−3(5)\frac{1}{2\left(-1\right)-3\left(5\right)}2(−1)−3(5)1
X === 1−2−15\frac{1}{-2-15}−2−151
X === 1−17\frac{1}{-17}−171
maka,
x2+y2−xy=(−1)2+(3)2−(−1)(3)x^2+y^2-xy=\left(-1\right)^2+\left(3\right)^2-\left(-1\right)\left(3\right)x2+y2−xy=(−1)2+(3)2−(−1)(3)
=1+9+3=1+9+3=1+9+3
=13=13=13