已知一个直角三角形的三边长成等比数列，则最小内角的正弦值为多少？
热心网友
直角边长：a，b (a= b)；斜边长：c；最小内角为角Bc^2 = a^2 + b^2, a^2 = bc == c^2 = b^2 + bc sin角B = b/c == 1 = (sin角B)^2 + sin角B== sin角B = (genhao5 -1)/2
已知一个直角三角形的三边长成等比数列，则最小内角的正弦值为多少？
直角边长：a，b (a= b)；斜边长：c；最小内角为角Bc^2 = a^2 + b^2, a^2 = bc == c^2 = b^2 + bc sin角B = b/c == 1 = (sin角B)^2 + sin角B== sin角B = (genhao5 -1)/2