Calculați: x-y-z, x+y-z şi-x-y + z, unde x = = a + b - c, y = a =-a-b+c,z=-a-b+c iar: a) a=5√5-3√2+2√3,b=√√5-4√√2-3√3, c= 2√5-√3-5√2; b) a=6√5-5√2-4√3, b=3√5-4√√2-6√3, c= -√√5 +2√3-6√2; c) a= 4√5-7√√2-3√3, b=-2√5 +5√2-7√√3, c= -3√5-3√√2-5√3.​

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