I. To calculate reaction at support A

$\Sigma \mathrm{Fy}=0$

$\mathrm{R}_{\mathrm{A}}-1-2-3=0$

$\mathrm{R}_{\mathrm{A}}=6 \mathrm{kN}$

II. SF calculation:

$SF at A=+6 \mathrm{kN}$

$\mathrm{C}_{\mathrm{L}}=+6 \mathrm{kN}$

$\mathrm{C}_{\mathrm{R}}=+6-1=5 \mathrm{kN}$

$\mathrm{D}_{\mathrm{L}}=+5 \mathrm{kN}$

$\mathrm{D}_{\mathrm{R}}=+5-2=3 \mathrm{kN}$

$\mathrm{B}_{\mathrm{L}}=+3 \mathrm{kN}$

$\mathrm{B}=+3-3=0(\therefore \mathrm{ok})$

III. BM calculation:

$\begin{aligned} \mathrm{BM} \text { at } \mathrm{B} &=0 \quad \because \mathrm{B} \text { is free end. …