sin (210)=sin (180+30)=-sin (30)=-0.5再者，你可以画图像解决.

2023年12月11日 · Understanding how to find the values of sine, cosine, tangent, cotangent, secant and cosecant at 210 degrees is an essential skill in trigonometry. This guide will walk through an effective method to evaluate all trigonometric ratios at 210 degrees and explain the intuition behind it.

Apply the reference angle by finding the angle with equivalent trig values in the first quadrant. Make the expression negative because sine is negative in the third quadrant. The exact value of sin(30) sin (30) is 1 2 1 2. The result can be shown in multiple forms.

2019年8月13日 · In this video, we learn to find the value of sin210. Here I have applied sin(180 + x) = -sin(x) identity to find the value of sin(210). The URL of the video ...

Use our sin(x) calculator to find the exact value of sine of 210 degrees - sin(210 °) - or the sine of any angle in degrees and in radians.

在第一象限中找出三角函数值与之相等的角，并使用这一参考角。 令表达式取负值，因为正弦在第三象限为负。 sin(30) sin (30) 的准确值为 1 2 1 2。 结果可以多种形式表示。 免费的数学问题解答者采用逐步解题讲解方式回答您的代数、几何、三角集合学、微积分以及统计学家庭作业问题，就像一位数学辅导老师那样为您提供帮助。

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2017年2月16日 · To obtain 210 degrees in radian multiply 210° by π / 180° = 7/6 π. Sin 210degrees = sin (7/6 × π). Our results of sin210° have been rounded to five decimal places. If you want sine 210° with higher accuracy, then use …

Calculate sin(210) sin is found using Opposite/Hypotenuse. Determine quadrant: Since 180 210 270 degrees it is located in Quadrant III. tan is positive. Determine angle type: 210 > 90°, so it is obtuse. sin(210) = -1/2. Special Angle Values

Let x be the sine of the 10 degree angle. Note the identity \sin(3x)=3\sin x-4\sin^3 x. This identity can be proved by using the addition laws for sine and cosin repeatedly, starting with \sin(3x)=\sin(2x+x)=\sin 2x \cos x +\cos 2x\sin x ...