
$\begin{aligned}
& 7^2=P^2+3^2+2 \times 3 \times P \cos \theta \quad \dots(1)\
& (\sqrt{19})^2=P^2+(-3)^2+2 \times(-3) \times P \cos \theta \quad \dots (2)
\end{aligned}addingweget68=2 P^2+18 \Rightarrow P=5$.
JEE Main 2007 — Mathematics Vectors & 3D Geometry
The resultant of two forces P N and 3 N is a force of 7 N. If the direction of 3 N force were reversed, the resultant would be 19 N. The value of P is
Held on 30 Apr 2007 · Verified 6 Jul 2026.
5 N
6 N
3 N
4 N
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