Hi! I've been trying to figure this out, but I'm not sure how I'd prove it..

Let V, W be two vector spaces, and F: V-->W a linear map. Let w_1, ..., w_n be elements of W which are linearly independent, and let v_1, ..., v_n be elements of V such that F(v_i)=w_i for i = 1, ..., n. Show that v_1, ..., v_n are linearly independent.

Help please! Thank you