Two point charges of \( 1 \, \text{nC} \) and \( 2 \, \text{nC} \) are placed at the two corners of equilateral triangle of side \( 3 \, \text{cm} \). The work done in bringing a charge of \( 3 \, \text{nC} \) from infinity to the third corner of the triangle is ________ \( \mu \text{J} \).
\( \dfrac{1}{4\pi\varepsilon_{0}} = 9 \times 10^{9} \, \text{N}\cdot\text{m}^{2}\,/\text{C}^{2} \)
