even_as
幼苗
共回答了16个问题采纳率:93.8% 举报
∵AB=1,AC=2,AD=3,∠DAB=∠DAC=60°,∠BAC=90°,
∴BC=
5 ,DB=
9+1-2×3×1×
1
2 =
7 ,DC=
9+4-2×3×2×
1
2 =
7
∴DE=
7-
5
4 =
23
2 ,AE=
5
2
∴cos∠ADG=
9+(
23
2 ) 2 -
5
4
2×3×
23
2 =
9
46
23
∵DG=2GE,
∴ DG=
23
3
∴在△ADG中,AG=
9+
23
9 -2×3×
23
3 ×
9
46
23 =
23
3
故答案为:
23
3
1年前
5