几道初中三角函数的题,1.计算:(sin45)^2+3/4tan30-tan45*cos602.(sin60)^2-cot45-tan60/cot60+cot303.计算:(tan30-sin45)/(cos45+cot60)4.求值:|1-cot35|-根号下(cot35)^2-cot456.已知:cotA=根号二,求(2sinA+cosA)/(2sinA-cosA)的值
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![几道初中三角函数的题,1.计算:(sin45)^2+3/4tan30-tan45*cos602.(sin60)^2-cot45-tan60/cot60+cot303.计算:(tan30-sin45)/(cos45+cot60)4.求值:|1-cot35|-根号下(cot35)^2-cot456.已知:cotA=根号二,求(2sinA+cosA)/(2sinA-cosA)的值](/uploads/image/z/6951551-23-1.jpg?t=%E5%87%A0%E9%81%93%E5%88%9D%E4%B8%AD%E4%B8%89%E8%A7%92%E5%87%BD%E6%95%B0%E7%9A%84%E9%A2%98%2C1.%E8%AE%A1%E7%AE%97%3A%28sin45%29%5E2%2B3%2F4tan30-tan45%2Acos602.%28sin60%29%5E2-cot45-tan60%2Fcot60%2Bcot303.%E8%AE%A1%E7%AE%97%3A%28tan30-sin45%29%2F%28cos45%2Bcot60%294.%E6%B1%82%E5%80%BC%EF%BC%9A%7C1-cot35%7C-%E6%A0%B9%E5%8F%B7%E4%B8%8B%28cot35%29%5E2-cot456.%E5%B7%B2%E7%9F%A5%EF%BC%9AcotA%3D%E6%A0%B9%E5%8F%B7%E4%BA%8C%2C%E6%B1%82%282sinA%2BcosA%29%2F%282sinA-cosA%29%E7%9A%84%E5%80%BC)
几道初中三角函数的题,1.计算:(sin45)^2+3/4tan30-tan45*cos602.(sin60)^2-cot45-tan60/cot60+cot303.计算:(tan30-sin45)/(cos45+cot60)4.求值:|1-cot35|-根号下(cot35)^2-cot456.已知:cotA=根号二,求(2sinA+cosA)/(2sinA-cosA)的值
几道初中三角函数的题,
1.计算:(sin45)^2+3/4tan30-tan45*cos60
2.(sin60)^2-cot45-tan60/cot60+cot30
3.计算:(tan30-sin45)/(cos45+cot60)
4.求值:|1-cot35|-根号下(cot35)^2-cot45
6.已知:cotA=根号二,求(2sinA+cosA)/(2sinA-cosA)的值
几道初中三角函数的题,1.计算:(sin45)^2+3/4tan30-tan45*cos602.(sin60)^2-cot45-tan60/cot60+cot303.计算:(tan30-sin45)/(cos45+cot60)4.求值:|1-cot35|-根号下(cot35)^2-cot456.已知:cotA=根号二,求(2sinA+cosA)/(2sinA-cosA)的值
1、原式=1/2+(根号3)/4-1/2=(根号3)/4
2、原式=3/4-1-3+(根号3)=〔-13+4(根号3)〕/4
3、原式={〔2(根号3)-3(根号2)〕/6}/{〔2+(根号2)〕/2}=-5+2(根号6)
4、原式=-1-1=-2
5、设sinA=a/c cotA=b/a
(2sinA+cosA)/(2sinA-cosA)=(2a+b)/(2a-b)
因为cotA=根号二,得b=(根号2)*a
则原式=(2+根号2)/(2-根号2)=3+2*(根号2)
累死我了,这根号真麻烦