A body of mass 4 kg experiences two forces $$\vec{F_1} = 5\hat{i} + 8\hat{j} + 7\hat{k}$$ and $$\vec{F_2} = 3\hat{i} - 4\hat{j} - 3\hat{k}$$. The acceleration acting on the body is:

Given:

F₁ = $$5\hat{i} + 8\hat{j} + 7\hat{k}$$
F₂ = $$3\hat{i} - 4\hat{j} - 3\hat{k}$$
mass m = 4 kg

First find net force:

$$F_{net}$$ = F₁ + F₂
= $$(5+3)\hat{i} + (8-4)\hat{j} + (7-3) \hat{k}$$
= $$8\hat{i} + 4\hat{j} + \hat{k}$$

Now acceleration:

a =$$\frac{F_{net}}{m}$$
= $$(8\hat{i} + 4\hat{j} + \hat{k})$$ / 4
= $$2\hat{i} + \hat{j} + \hat{k}$$

So the acceleration is:

$$2\hat{i} + \hat{j} + \hat{k}$$