3/(√7-2)
=3×(√7+2)/(√7-2)(√7+2)
=3×(√7+2)/(√7×√7-2×2)
=3×(√7+2)/(7-4)
=3×(√7+2)/3
=√7+2
∵√7≈2.65 ∴整数部分为2+2=4
∴小数部分为√7+2-4=√7-2
3/(√7-2)
=3×(√7+2)/(√7-2)(√7+2)
=3×(√7+2)/(√7×√7-2×2)
=3×(√7+2)/(7-4)
=3×(√7+2)/3
=√7+2
∵√7≈2.65 ∴整数部分为2+2=4
∴小数部分为√7+2-4=√7-2