在高一的三角函数中,我们学习了二倍角公式、半角公式以及后面的解斜三角形。而高二学习了曲线方程,其中在椭圆、双曲线中知道了离心率、准线方程、渐近线,还有其中的a,b,c的关系。而在解这类曲线方程中,绝大部分学生用它们的第一 In the first-trigonometric trigonometric function, we have studied the double-diagonal formula, the half-angle formula, and the later solution oblique triangle. The second year learned the curve equation, in which the eccentricity, the quasi-line equation, the asymptote, and the relationship between a, b, and c were known in the elliptic and hyperbolic curves. While solving this type of curve equation, the vast majority of students use their first