In rectangular ABCD, BC = 4, BG is perpendicular to diagonal AC and intersects AC, ad and ray CD at points e, F, G, ab = x respectively. (1) when point G coincides with point D, calculate the value of X; (2) when point F is the midpoint of AD, calculate the value of X and the sine value of ∠ ECF
(1) When point G coincides with point D, point F also coincides with point D. in ∵ rectangular ABCD, AC ⊥ BG, ∵ quadrilateral ABCD is square, ∵ BC = 4, ∵ x = AB = BC = 4; (2) ∵ point F is the midpoint of AD, and ad = BC = 4, ∵ AF = 12ad = 2,
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