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Resultant force

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Two forces $P_1=\\var{P1}\\;\\text{kN}$ and $P_2=\\var{P2}\\;\\text{kN}$ are applied at Point B of beam AB

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(a) Using the law of cosines:

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$R^2=(\\var{P1}\\;\\text{kN})^2+(\\var{P2}\\; \\text{kN})^2-2(\\var{P1}\\;\\text{kN})(\\var{P2}\\;\\text{kN})\\cos 80^\\circ$

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$R=\\var{R}\\;\\text{kN}$  \u25c0

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(b) Using the law of sines

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$\\dfrac{\\sin \\gamma}{\\var{P1}\\;\\text{kN}}=\\dfrac{\\sin 80^\\circ}{R}$

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$\\gamma=\\var{gamma}^\\circ$

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In the triangle

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$\\beta+\\gamma+80^\\circ=180^\\circ$

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$\\beta=\\var{beta}^\\circ$

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$\\phi=180^\\circ-\\beta-50^\\circ=\\var{phi}^\\circ$

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$\\phi=\\var{phi}^\\circ$ \u29aa \u25c0

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;;precround(90+a-degrees(arcsin({P2}/{R}*sin(radians(180-a-b)))),2)

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Determine the magnitude of their resultant (in kN) using the triangle rule.

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Determine the direction of the resultant. (in degrees, measured from the horizontal axis  )

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