已知三角形ABC,它的面积是6,外接圆的半径为3,内切圆的半径为1,求sinA+sinB+sinC为多少?请问(古树声的月):那个S = (a+b+c)* 1/2 = 6 怎么来的啊?呵呵
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![已知三角形ABC,它的面积是6,外接圆的半径为3,内切圆的半径为1,求sinA+sinB+sinC为多少?请问(古树声的月):那个S = (a+b+c)* 1/2 = 6 怎么来的啊?呵呵](/uploads/image/z/8673630-6-0.jpg?t=%E5%B7%B2%E7%9F%A5%E4%B8%89%E8%A7%92%E5%BD%A2ABC%2C%E5%AE%83%E7%9A%84%E9%9D%A2%E7%A7%AF%E6%98%AF6%2C%E5%A4%96%E6%8E%A5%E5%9C%86%E7%9A%84%E5%8D%8A%E5%BE%84%E4%B8%BA3%2C%E5%86%85%E5%88%87%E5%9C%86%E7%9A%84%E5%8D%8A%E5%BE%84%E4%B8%BA1%2C%E6%B1%82sinA%2BsinB%2BsinC%E4%B8%BA%E5%A4%9A%E5%B0%91%3F%E8%AF%B7%E9%97%AE%28%E5%8F%A4%E6%A0%91%E5%A3%B0%E7%9A%84%E6%9C%88%29%3A%E9%82%A3%E4%B8%AAS+%3D+%28a%2Bb%2Bc%29%2A+1%2F2+%3D+6+%E6%80%8E%E4%B9%88%E6%9D%A5%E7%9A%84%E5%95%8A%3F%E5%91%B5%E5%91%B5)
已知三角形ABC,它的面积是6,外接圆的半径为3,内切圆的半径为1,求sinA+sinB+sinC为多少?请问(古树声的月):那个S = (a+b+c)* 1/2 = 6 怎么来的啊?呵呵
已知三角形ABC,它的面积是6,外接圆的半径为3,内切圆的半径为1,求sinA+sinB+sinC为多少?
请问(古树声的月):那个S = (a+b+c)* 1/2 = 6 怎么来的啊?呵呵
已知三角形ABC,它的面积是6,外接圆的半径为3,内切圆的半径为1,求sinA+sinB+sinC为多少?请问(古树声的月):那个S = (a+b+c)* 1/2 = 6 怎么来的啊?呵呵
设三角形的三边长为a,b,c,r=1,R=3,S=6
S = (a+b+c)* 1/2 = 6
a+b+c = 12
2R=a/sinA=b/sinB=c/sinC
a=2R×sinA = 6sinA
b=2R×sinB = 6sinB
c=2R×sinC = 6sinC
a+b+c = 12 = 6(sinA+sinB+sinC)
sinA+sinB+sinC=2
内切圆的性质就是到三角形三边的距离都相等
S = (a*r+b*r+c*r)* 1/2 =(a+b+c)* 1/2 = 6
设三角形的三边长为a,b,c,r=1,R=3,S=6
S = (a+b+c)* 1/2 = 6
a+b+c = 12
2R=a/sinA=b/sinB=c/sinC
a=2R×sinA = 6sinA
b=2R×sinB = 6sinB
c=2R×sinC = 6sinC
a+b+c = 12 = 6(sinA+sinB+sin...
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设三角形的三边长为a,b,c,r=1,R=3,S=6
S = (a+b+c)* 1/2 = 6
a+b+c = 12
2R=a/sinA=b/sinB=c/sinC
a=2R×sinA = 6sinA
b=2R×sinB = 6sinB
c=2R×sinC = 6sinC
a+b+c = 12 = 6(sinA+sinB+sinC)
sinA+sinB+sinC=2
内切圆的性质就是到三角形三边的距离都相等
S = (a*r+b*r+c*r)* 1/2 =(a+b+c)* 1/2 =6
应该对吧!相信我!
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