Full score training 1 when a 1 4, b 4, find the value of the algebraic formula a b 1 2ab .

a=1 4,b=4, find the algebraic formula a (-b ) 1 2ab ) a=b (-1) substitution:

b^(-3+6)-1/8b(-3+6)

7/8b^3

7x4^3/8

2.（-x）²x（-2y）³+2xy）²（x）³y-8x^3y^3-4x^5y^3

3. 9^n×（-1/27）^n+1×3^n+2(9x(-1/27))^n+3^n+2

3)^(n)+3^n+2

4x10^10

6.(-x) 6-(-3x) Question Supplement:

x^6-9x^6+8x^6

7.(-2x³）²3²）³2x）³·x³）4x^6-27x^6-8x^6

31x 6 is much more convenient to do this kind of problem, first determine the positive and negative properties of the monomial, and then use the properties of the operation to calculate.

1.When a=1 4, b=4, find the value of the algebraic formula a (-b ) 1 2ab ).

a³(-b³)²1/2ab²)³

a³b^6-1/8a³b^6

9/8a³b^6

When a=1 4 b=4.

9/8a^3b^6=-9/8(1/4)^3*4^6=-9/8*4³=-36

2.（-x）²x（-2y）³+2xy）²（x）³y=x²*(8y³)-4x²y²*x³y=-8x²y³-4x^5y³

3. 9^n×（-1/27）^n+1×3^n+2=-1/36.（-x）^6-（-3x³）²=x^6-9x^6+8x^6=0

Multiply the first equation a to get a three times + a quadratic - a = 0 and add the first equation to give a three times + 2a two = 1 plus 5 equals 6

Knowing that a and b satisfy b = a -4 + 4-a + 4 a-2, find the algebraic equation |a-2b|+ ab.

a, b satisfies b = a -4 + 4-a +4 a -2 a -4 0 4-a 0 a-2≠ a=-2

b=-1a-2b|+√ab=|-2+2|+√2=√2

May I ask if it is ( A 3)-4 or (A 3-4) Alas, I don't read a book just look at it, but unfortunately I can't understand it, can you tell me?

a 1 = 3a, b 1 = 3b, then: a, b are the two roots of the equation x 1 = 3x, that is, x 3 x 1 = 0, then:

a b = 3 and ab = 1

1/a²＋1/b²=[a²＋b²]/(ab)²=[(a＋b)²－2ab]/(ab)²=(3x3-2x1)/1x1=7

a +1 = 3a, b +1 = 3b, subtract a -b = 3 (a-b), a≠b, a + b = 3.

Add the two formulas to get a +b +2 = 3 (a + b), a + b = 7, and then (a + b) = a +b + 2ab to get ab = 1.

1/a²+1/b²=(a²+b²)/(ab)²=7。