1
a)c{-3;6}⇒1/3c{-1;2}
b{2;-2}⇒-b{-2;2}
a=1/3c-b={-3;4}
б)/a/=√(9+16)=√25=5
в)a=-3i+4j
2
AB=
BC=
CD=
AD=
AB=CD U BC=AD⇒ABCD-параллелограмм
P=2(AB+BC)=2(4+√13)=8+2√13
3
AB{2-m;6} ,BC{-3;6}
AB=BC⇒2-m=-3⇒m=2+3=5
-3/5*7/11-2/5*7/11=
-21/55-14/55=-35/55=-7/11
8х=19
х=19/8
4х-2=-2
4х=0
х=0
9 ^ ( 3 + x ) = 1,8 * 5 ^ ( 3 + x )
9/5 ^ ( 3 + x ) = 1,8
1,8 ^ ( 3 + x ) = 1,8
3 + x =1
x = - 2