Răspuns:
a) (m+1)/2=3/m
m²+m=6
m²+m-6=0
m1=2
m2= -3
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b)lbl=√(2²+m²)=8
Ridici la patrat
(4+m²)=64
m²=64-4
m²=60
m=√60=√15*4=
±2√15
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m=2
a=(2+1)i+3j=3i+3j
2a=2(3i+3j)=6i+6j
b=2i+3j
3b=3(2i+3j)=6i+9j
2a+3b=6i+6j+6i+9j=
`12i+15j
Explicație pas cu pas: