Jawabanmu

2014-09-09T00:53:49+07:00
2*2+5*5+2.2.5.cos120 diakarkan --> 4+25+(-10) diakarkan = akar 19
2014-09-09T06:04:40+07:00
Dik
A = 2 N
B = 5 N
α  = 120
R =?

R^2 = A^2 + B^2 + 2.A.B cos 120
R^2 = 2^2 + 5^2 + 2.2.5.(-0,5)
R^2 = 4 + 25 -10
R^2 = 19
R     = √19
R    = 4,36 satuan


semoga membantu ^-^