sin0 =0，cos0 = 1;sin90 =1，cos90 = 0;sin180 =0，cos180 =-1 .原因如下：1.当角度为0时，角度的两侧重合，y轴上的值为0，因此sin 0 = 0。2.cosx=邻边/斜边。当x=0时，斜边和邻边相等，所以Cos0 = 1。3.sinα=r/y，其中r是单位圆的半径。当α=90度时，r=y...
A项,\sin(180\degree+\alpha)=-\sin\alpha,故A项错误; B项,\cos(180\degree-\alpha)=-\cos(-\alpha)=-\cos\alpha,故B项错误; C项,\tan(180\degree+\alpha)=\tan\alpha,故C项正确; D项,\cos(180\degree+\alpha)=-\cos\alpha,故D项错误。 故本题正确答案为C。反馈...
\begin{cases} sin(180 - \alpha) = sin \alpha \\ cos(180 - \alpha) = -cos \alpha \end{cases} 证明:把sin180^\circ = 0,cos180^\circ = -1带入和差角公式即可证明。 (5)360°补角公式 \begin{cases} sin(360 - \alpha) = -sin \alpha \\ cos(360 - \alpha) = cos \alpha \end...
Densin-180 Forms a Ternary Complex with the α-Subunit of Ca2+/Calmodulin-Dependent Protein Kinase II and α-Actinin Kennedy MB ( 2001 ) Densin-180 forms a ternary complex with the (alpha)-subunit of Ca2+/calmodulin-dependent protein kinase II and (alpha)-actinin ... RS Walikonis,A Og...
sinπ等于0。以下是详细的解释：一、正弦函数的基本定义 正弦函数是三角函数的一种，它描述了一个角与直角三角形的边长之间的关系。在数学中，π代表一个特定的角度，约等于180°。根据正弦函数的周期性，我们知道正弦函数的周期是2π，也就是说sin = sinα。这意味着当我们增加&...
360°等同于2π rad,也就是1°等同于π/180rad,或者1rad等同于180/π ° 得到换算公式: a rad= [(180/π)*a]° b°=[(π/180)*b]rad 例一 举个具体例子会更加直观: 假设圆A的半径为5厘米,那么弧度为π/6(也就是30°)大小的角,它对应的弧长为: ...
化简\sin (180^ \circ \alpha )的结果是()A. < underline> \sin a< /underline> B. < underline> \cos \alpha < /underline> C. -< underline> \sin a< /underline> D. -< underline> \cos \alpha < /underline> 相关知识点: 试题来源: 解析 C 反馈 收藏 ...
Robison AJ, Bass MA, Jiao Y, MacMillan LB, Carmody LC, Bartlett RK, Col- bran RJ (2005b) Multivalent interactions of calcium/calmodulin- dependent protein kinase II with the postsynaptic density proteins NR2B, densin-180, and alpha-actinin-2. J Biol Chem 280:35329 -35336....
Interferon alpha was first produced as an antiviral molecule in the 1950s; and, found to have anti-tumor and anti-proliferative activity through inhibition of the JAK/STAT/MAPK pathways [12], as well as apoptosis through the FAS pathway [13]. Interferon has since been utilized in the ...
我们知道在直角三角形中,sin60\degree=\frac{\root \of {3} }{2},当\alpha 不是锐角时,sin\alpha 的值也是存在的,例如:sin120\degree=\frac{\root \of {3} }{2},sin180\degree=0,sin240\degree=-\frac{\root \of {3} }{2},sin300\degree=-\frac{\root \of {3} }{2},sin360\deg...