Question

已知a b c是三角形的三边,|化简根号(a²-b²-c²)-

Answer 1

√(a-b-c)²-2√（a²+b²+c²-2ab-2bc+2ac）+3|a+b-c|

=√(a-b-c)²-2√（a+c-b)²+3|a+b-c|

=|a-b-c|-2|a+c-b|+3|a+b-c|

∵a,b,c是三角形abc的三边

∴ab,a+b>c

∴|a-b-c|-2|a+c-b|+3|a+b-c|

=(b+c-a)-2(a+c-b)+3(a+b-c)

=b+c-a-2a-2c+2b+3a+3b-3c

=6b-4c