(√6-√2)²
=√6²-2×√6×√2+√2²
=6-2×√(6×2)+2
=8-2×√(2²×3)
=8-2×2√3
=8-4√3
4√12÷[-√(1/3)]
=4÷(-1)×√(12÷1/3)
=-4×√36
=-4×6
=-24
√18÷√8×√(27/2)
=√(18÷8×27/2)
=√(18×1/8×27/2)
=√(243/8)
=√[(9/4)²×6]
=(9/4)×√6
=(9√6)/4
(-7/4√24)(-2/7√6)
=-7/4×(-2/7)×√(24×6)
=1/2×√12²
=12×1/2
=6
√6(√24-√2)
=√6×√24-√6×√2
=√(6×24)-√(6×2)
=√12²-√(2²×3)
=12-2√3
(√7-3)²-(√7+3)²
=[(√7-3)+(√7+3)] [(√7-3)-(√7+3)]
=(√7-3+√7+3)(√7-3-√7-3)
=2√7×(-6)
=-12√7