About Lesson
(1)
Convert the following trigonometric functions to acute trigonometric functions.
化下列各三角函数为锐角三角函数
(a)
(b)
(c)
(d)
)
(e)
(f)
Convert the following trigonometric functions to acute trigonometric functions.
化下列各三角函数为锐角三角函数
(a)

(b)

(c)

(d)

(e)

(f)

答案 Answer
(a) 
(b)
(c)
(d)
(e)
(f)

(b)

(c)

(d)

(e)

(f)

(2)
Given that
Given that
*** QuickLaTeX cannot compile formula: tanA= \frac{8}{15} *** Error message: Unicode character (U+2061) leading text: $tan
, where is in the third quadrant, calculate
and
已知
*** QuickLaTeX cannot compile formula: tanA= \frac{8}{15} *** Error message: Unicode character (U+2061) leading text: $tan
, 且A 在第三象限, 计算 和
。
答案 Answer


(3)
Given that
<
<
, and
, find the value of
Given that




*** QuickLaTeX cannot compile formula: \frac{13 sinA+5 secA}{3 tanA+cose A} *** Error message: Unicode character (U+2061) leading text: $\frac{13 sinA+5 secA}{3 tanA+cose A}
已知 <
<
以及
, 求
*** QuickLaTeX cannot compile formula: \frac{13 sinA+5 secA}{3 tanA+cose A} *** Error message: Unicode character (U+2061) leading text: $\frac{13 sinA+5 secA}{3 tanA+cose A}
的值
答案 Answer

(4)
If
, calculate the values of
and
.
若
, 试计算
和
的值。
If



若



答案 Answer


(5)
If
, calculate the values of
.
若
, 求
的值.
If


若


答案 Answer


当
在第四象限
(6)
If 12tan x = 5, sin x < 0, calculate the value of
If 12tan x = 5, sin x < 0, calculate the value of
*** QuickLaTeX cannot compile formula: \frac{2sinx+secx}{4 cotx-3 cosx} *** Error message: Unicode character (U+2061) leading text: $\frac{2sinx+secx}{4 cotx-3 cosx}
若 12tan x = 5, sin x < 0, 求
*** QuickLaTeX cannot compile formula: \frac{2sinx+secx}{4 cotx-3 cosx} *** Error message: Unicode character (U+2061) leading text: $\frac{2sinx+secx}{4 cotx-3 cosx}
的值。
答案 Answer
