Question

谁有数学必修四三角恒等变换复习参考题答案

Answer 1

1. a||b,则?sinxcosx-?×?=0；   sin2x=1;  2x=2kπ+π/2;

2. x=kπ+π/4;所以锐角x=π/4;

3. 2.f(x)=6cos2x-√3sin2x=3cos2x+3-√3sin2x=2√3sin(π/3-2x)+3

4. f(a)=3-2√3;

5. 2√3sin(π/3-2a)+3=3-2√3

6. sin(π/3-2a)=-1

7. sin(2a-π/3)=1

8. 2a-π/3=2kπ+π/2

9. a=kπ+5π/12;

10. a=5π/12

11. (4/5)a=π/3

12. tan(4a/5)=tanπ/3=√3