计算:1.tan30°*cos60°+sin^245°
3.sin60°-cos45°分之sin30°-根号(1-tan60°)^2-tan45°
4.(3分之2)^-1+(π-3.14)^0-2sin60°-根号12+|1-3倍根号3|
5.2sin30°-(2分之1)^-1·|1-tan60°|+根号3+1分之2
6.cos45°-cos60°分之sin30°-2sin45°+根号3tan30° 展开
tan30°*cos60°+sin^245°
=√3/3 ×1/2 +(√2/2)方
=√6/6 +1/2
sin^245°+sin^260°+根号6cos30°·cos45°
=(√2/2)^2+(√3/2)^2+√6×√3/2 ×√2/2
=1/2 +3/4+3/2
=11/4
3.sin60°-cos45°分之sin30°-根号(1-tan60°)^2-tan45°=√3/2 -(√2/2)分之(1/2) -tan60°+1-1
=√3/2 -√2/2 -√3
=-√2/2-√3/2
4.(3分之2)^-1+(π-3.14)^0-2sin60°-根号12+|1-3倍根号3|=2分之3 +1-2×√3/2-2√3 +3√3-1
=2分之5 -√3-2√3+3√3-1
=2分之3
5.2sin30°-(2分之1)^-1·|1-tan60°|+根号3+1分之2=2×1/2 -2×(√3-1) +2(√3-1)/[(√3)^2-1^2]
=1 -2√3 +2 -√3+1
=4-3√3
6.cos45°-cos60°分之sin30°-2sin45°+根号3tan30°=√2/2 -(1/2)分之(1/2) -2×√2/2 +√3×√3/3
=(√2/2 -√2 ) -1+1
=-√2/2
第五题楼下是正确的。
2015-01-23 · 知道合伙人教育行家
= √3/3*1/2 +(√2/2)²
= √3/6+1/2
= (3+√3)/6
2.sin^245°+sin^260°+根号6cos30°·cos45°
= (√2/2)²+(√3/2)²+√6*√3/2*√2/2
=1/2+3/4+6/4
= 11/4
3.sin60°-cos45°分之sin30°-根号(1-tan60°)^2-tan45°
= √3/2 - (1/2)/(√2/2) - √(1-√3)² - 1
= √3/2-√2/2-√3+1-1
= -(√3+√2)/2
4.(3分之2)^-1+(π-3.14)^0-2sin60°-根号12+|1-3倍根号3|
= 3/2 + 1 - 2*√3/2 -2√3 + 3√3-1
= 3/2 + 1 - √3 -2√3 + 3√3-1
= 3/2
5.2sin30°-(2分之1)^-1·|1-tan60°|+根号3+1分之2
= 2*1/2 - 2 *|1-√3| + 2/(√3+1)
= 1 -2(√3-1) + 2(√3-1)/{(√3+1)(√3-1)}
= 1 -2(√3-1) + 2(√3-1)/(3-1)
= 1 - √3 + 1
= 2-√3
6.cos45°-cos60°分之sin30°-2sin45°+根号3tan30°
= √2/2 - (1/2)/(1/2) - 2*√2/2 + √3*√3/3
= √2/2 - 1 - √2 + 1
= -√2/2
=六分之根号3-sin65
同学你好,如果问题已解决,记得右上角采纳哦~~~您的采纳是对我的肯定~谢谢哦