）Try to calculate the values of √ 11-2, √ 1111-22, √ 111111-222 with calculator, and explain the change rule

）Try to calculate the values of √ 11-2, √ 1111-22, √ 111111-222 with calculator, and explain the change rule

√(1......1-2......2)
=√(1......10......0-1......1)____ Break down item
=√[1......1•(10......0-1)]___________ Extracting common factors
=√(1......1•9......9)
=√(1......1²•9)________________________ Prescription
=1......1•3
=3......3
That is to say, there are n ones in it, and the result is n-1 three
√1…… (n 1) - 2 (N 2)=
…… (n 3)

If a and B are specified, 4AB can be obtained by "△". For example, 2 △ 4 = 4 * 2 * 4 = 32 (1) find the value of (- 4) △ 5

（-4）△5
=4×（-4）×5
=-80

Specify an operation: a ⁃ B = ab-a-b + 1, for example, 2 ⁃ 3 = 2 × 3-2-3 + 1, please calculate the value of 4 ⁃ 5-5 ⁃ 4

33