Given that the point (a, b) is on the line x + 3y-2 = 0, then the minimum value of u = 3 ^ A + 27 ^ B + 3 is Please write down the process

Given that the point (a, b) is on the line x + 3y-2 = 0, then the minimum value of u = 3 ^ A + 27 ^ B + 3 is Please write down the process

a+3b-2=0,3b=2-a
u=3^a+27^b+3=3^a +3^(3b)+3
=3^a+3^(2-a)+3
=3^a+9/3^a+3
=(3^a/2 -3/3^a/2)^2+6+3
=(3^a/2 -3/3^a/2)^2 +9
When 3 ^ A / 2 = 3 / 3 ^ A / 2, that is, 3 ^ a = 3, a = 1, u has a minimum value of 9

Let x belong to [0,2], then the maximum and minimum of x power + 2 of x power - 3 times 2 of function y = 4

Let t = 2 ^ x, then t ∈ [1,4]
y=t^2-3t+2=(t-3/2)^2-1/4
When t = 3 / 2, Ymin = - 1 / 4
When t = 4, ymax = 6

If the sum of 17 consecutive integers is 306, then the sum of the 17 consecutive integers immediately after the 17 integers is equal to 306______ ．

The sum of 17 consecutive integers is 306, then the sum of the following 17 consecutive integers is 306 + 17 × 17 = 595

If (a + b) & # - 4 (a + B-1) = 9, then the relation between a and B

(a+b)²-4（a+b-1）=9
(a+b)²-4(a+b)+4-9=0
(a+b)²-4(a+b)-5=0
(a+b+1)(a+b-5)=0
A + B = - 1, or a + B = 5

63 times (5 out of 9 plus 4 out of 21 minus 3 out of 7)

If the algebraic formula x ^ 2 + ax + B can be factorized into (x + 4) (X-7), try to find the value of a and B

The brackets of (x + 4) (X-7) are removed
(x+4)(x-7)=x^2-3x-28
If x ^ 2 + ax + B = (x + 4) (X-7), then,
There must be a = - 3, B = - 28

How much is seven eighths multiplied by 0.375 divided by seven eighths

(7/18)*0.375/(7/8)=7/18*(3/8)/(7/8)=3/18 =1/6

The surface area of a cuboid is 56 square centimeters, which can be cut into three identical cubes. What's the surface area of each cube?

Three cubes have: 6 × 3 = 18 faces
When the cuboid is cut into 3 cubes, 4 faces are added
So 56 square centimeters is exactly: 18-4 = 14 surface area
Area of each surface: 56 △ 14 = 4 (square centimeter)
Surface area of each cube: 4 × 6 = 24 (square centimeter)

On the left side of a balance is equal to the right side. On the right side, there is a 100g weight and X weights. On the left side, there are three X weights. How many equations are used to find x equal to

3x=100+x
3x-x=100
2x=100
x=100÷2
x=50

A three digit number can be divided by 3 and 5 at the same time. If it is odd, what is the maximum number? If it is even, what is the minimum number?
Today

Miraculous deeds,
The smallest number divisible by 3 and 5 is their least common multiple
3×5＝15
The number of multiples of 15 in three digits is as follows:
1000 △ 15 ≈ 66 (pieces)
The largest of the odd numbers is:
15×66－15＝975
The smallest of the even numbers is:
15×8＝120