Question

高一的同角三角函数的关系的题目，拜托了！

Answer 1

1. 原式=(4tana-2)/(5+3tana)=10 , 4tana-2=50+30tana, tana=-2

2. (sinx+cosx)^2=2, sinxcosx=1/2 , [(sinx)^2+(cosx)^2]^2=1=(sinx)^4+2(sinxcosx)^2+(cosx)^4

   (sinx)^4+(cosx)^4=1-2(sinxcosx)^2=1/2

3. 4tana+6sinβ=14

   tana-6sinβ=1,        5tana=15,  tana=3, sina=3cosa, sin^2a=9cos^2a, sina=3√10/10

4. sina|sina|+cosa|cosa|=-1 , 2kπ+π<a<2kπ+3π/2