Answer
$\langle-1.5321,-1.2856\rangle$
Work Step by Step
$u=\langle a,b\rangle=\langle |u|\cos\theta,|u|\sin\theta\rangle$
Substitute $|u|=2$ and $\theta=-140^\circ$:
$\langle a,b\rangle=\langle2\cos (-140^\circ),2\sin(-140^\circ)\rangle $
$\langle a,b\rangle =\langle-1.5321,-1.2856\rangle$
