sin+cos+tan35度公式

邱柴乐1919sin2+cos3+tan4 怎么算??
潘览泽19735123367 ______ 用计算器算: sin2≈0.9093 cos3≈-0.9900 tan4≈1.1578 加起来既得:0.0771

邱柴乐1919sin,cos,tan,cot,分别是哪边对哪边 -
潘览泽19735123367 ______ sin@是对边比斜边cos@是临边比斜边tan@是对边比临边cot@是临边比对边不要死记,画图,理解

邱柴乐1919sin(π/3)+cos(π/6)+tan(π/4) 计算 等于多少··步骤 -
潘览泽19735123367 ______ sin(π/3)+cos(π/6)+tan(π/4)=sin60°+cos30°+tan45°=√3/2+√3/2+1=√3+1 谢谢,希望采纳

邱柴乐1919先估算结果的符号,再进行计算 sin2+cos3+tan4 -
潘览泽19735123367 ______ 0<2<Pi, sin2>0 Pi/2<3, -1<cos3<04>Pi/4, tan4>1 由此得cos3+tan4>0 又sin2>0 所以sin2+cos3+tan4 >0

邱柴乐19192sin60°+4cos45°+3tan30°等于? -
潘览泽19735123367 ______ sin60°=根号3/2cos45°=根号2/2tan30°=根号3/32sin60°+4cos45°+3tan30°=2*根号3/2+4*根号2/2+3*根号3/3=根号3+2*根号2+根号3=2*根号3+2*根号2

邱柴乐1919计算下列各式的值:(1)tan( - 135°)sin( - 450°)+cos240°;(2)sin( - 7π2)+cos13π3 - tan23π6. -
潘览泽19735123367 ______[答案] (1) tan(-135°) sin(-450°)+cos240°= tan(-180°+45°) sin(-360°-90°)+cos(180°+60°)= tan45° -sin90°-cos60°= 1 -1-12=- 2 3; (2)sin(- 7π 2)+cos 13π 3-tan 23π 6=sin(-4π+ π 2)+cos(4π+ π 3)-tan(4π- π 6) =sin π 2+cos π 3+tan π 6=1+ 1 2+ 3 3= 3 2+ 3 3.

邱柴乐1919已知sin(α - π/4)=(7根号2)/10,cos2α=7/25,求sinα+cosα及tan(α+π/3)的值. -
潘览泽19735123367 ______ sin(α-π/4)=7√2/10=sinαcosπ/4-cosαsinπ/4=sinα√2/2-cosα√2/2 =√2/2(sinα-cosα)=7√2/10 sinα-cosα=7/5 cos2α =cos^2(α)-sin^2(α)=(sinα-cosα)(sinα+cosα)=7/257/5(sinα+cosα)=7/25 sinα+cosα=1/5

邱柴乐1919sinα+cosα=(根号2)/3求tanα -
潘览泽19735123367 ______ 解:sinα+cosα=√2/3(sinα+cosα)^2=2/9 sin^2α+cos^2α+2sinαcosα=2/92sinαcosα=-7/9 sin2α=-7/9 由万能公式可得 sin2α=2tanα/(1+tan^2α)=-7/918tanα=-7(1+tan^2α)7tan^2α+18tanα+7=0 tanα=(-18±8√2)/14==(-9±4√2)/7

邱柴乐1919sin( - 11/6π)+cos(8/3)tanπ/4= -
潘览泽19735123367 ______ 解:题目应该是: sin(-11/6π)+cos(8/3π)tanπ/4 = sin[(-2π+(1/6)π]+cos(3π-π/3)tanπ/4 =sin(1/6)π+[-cosπ/3 *1 =1/2 - 1/2 *1=0

邱柴乐1919若sinθ+cosθ=2,则tan(θ+π3)的值是 - _ - . -
潘览泽19735123367 ______[答案] ∵sinθ+cosθ= 2,平方可得sin2θ=1, 2sinθcosθ sin2θ+ cos2θ=1, ∴ 2tanθ tan2θ +1=1,tanθ=1. ∴tan(θ+ π 3)= tanθ+3 1-3tanθ= 1+3 1-3=-2- 3, 故答案为-2- 3.