计算r²+(2√2r-R+2r)²=(R-r)²,r/R?

r²+(2√2r-R+2r)²=(R-r)²(R-r)²-(2√2r-R+2r)²=r²(2√2+1)r*(-2√2r-3r+2R)=r²-(2√2+1)(2√2+3)r+2(2√2+1)R=r2(2√2+1)R=[(2√2+1)(2√2+3)+1]r2(2√2+1)R=(12+8√2)rr/R=(2√...