34788535
幼苗
共回答了13个问题采纳率:92.3% 举报
(1) 6 4
1
3 - (-
2
3 ) 0 +
3 125
+lg2+lg50+ 2 1+ log 2 3 = (4 3 )
1
3 -1+ (5 3 )
1
3 +lg(2×50)+2× 2 log 2 3 =4-1+5+2+2×3=16.
(2)
tan80°-tan20°+tan(-60°)
tan80°tan20° =
tan(80°-20°)(1+tan80°tan20°)-tan(60°)
tan80°tan20° =
3 tan80°tan20°
tan80°tan20° =
3 .
1年前
5