Answer: √7
Explanation:
cos A = adj / hyp = √2 / 3
We need to find the angle A before we proceed
cos A = 0.4714
A = arccos(0.4714)
A =61.87
adj =√2 hyp = 3 opp =a
sin A = opp / hyp
sin61.87 = a / 3
cross multiply
a = 3 sin 61.87
a = 3 × 0.88188
a =2.6456
a = √7