It is known that the square root of 2a-1 is ± 3, and the square of 3A + B is ± 4. The process of finding the square root of a + 2B

2a-1=9
2a=10
a=5
3a+b=16
3*5+b=16
b=1
√（a²+2b）
=√（5²+2*1）
=√27
=±3√3

Given that the square root of 2a-1 is ± 3, the arithmetic square root of 3A + B-1 is 4, find the square root of a + the square root of 2B

The square root of 2a-1 is ± 3,
So 2a-1 = 9 leads to a = 5
The arithmetic square root of 3A + B-1 is 4
So 3A + B-1 = 16, B = 2
So the square root of a + the square root of 2B = 25 ± 2 = 27 or 23

As shown in the figure, in △ ABC, ad is the height on the edge of BC, and the extension line of ad = BD, ed = CD, be intersects AC at F

In △ BDE and △ ADC, BD = ad ∠ ADB = ∠ adced = ed, △ BDE ≌ △ ADC (SAS), EBD = DAC, EBD + bed = 90 degree, DAC + bed = 90 degree, bed = AEF (equal to vertex angle), AEC + AEF = 90 degree, AFE = 90 degree, namely BF ⊥ AC

Let a not be equal to B. compare the sizes of the algebraic expressions A2 (a + 1) + B2 (B + 1) and a (A2 + b) + B (B2 + a)

How to make a quadrilateral equal to twice the area of a known triangle
Make a quadrilateral whose area is twice the area of a known triangle

Take one side of the triangle as the symmetry axis to make the original triangle

If f (x ∧ 5) = lgx, then f (2) is equal to

F (x ^ 5) = lgx does not mean f (x) = lgx
Generally speaking, the "F" in the function f (x) is a general symbol used to represent the corresponding rule of dependent variable and variable (x), which can also be written as h, G , is just a letter, can also be expressed as: H (x), G (x)
For example: y = lgx + 1, every value of X has a corresponding y value, which is obtained by the corresponding relationship of y = f (x) = lgx + 1
f(x^5)＝lgx
This is a compound function, which is obtained by combining f (T) = LG [T ^ (1 / 5)] and T = x ^ 5;
So in fact, the analytic expression of F (x) should be: F (x) = LG [x ^ (1 / 5)], X is just a sign of an unknown number!
When you replace X in F (x) with x ^ 5, f (x ^ 5) = LG [(x ^ 5) ^ (1 / 5)] = lgx
For example, let x = 2, the results are different in two cases
For the formula F (x) = LG [x ^ (1 / 5)], x = 2 is: F (2) = LG [2 ^ (1 / 5)] = 0.2lg2
For f (x ^ 5) = LG [(x ^ 5) ^ (1 / 5)] = lgx, x = 2 is f (2 ^ 5) = f (32) = LG [32 ^ (1 / 5)] = LG2
Another example is: the domain of F (√ (x + 1)) is [0,3], and the domain of F (x) is obtained
F (√ (x + 1)) is also composed of two functions: F (T) and T = √ (x + 1)
The domain of F (√ (x + 1)) is [0,3], which indicates that the domain of X in function T = √ (x + 1) is [0,3], so 1

A bamboo pole is less than 9 meters long. Measure it from one end to 5 meters and make a mark A. measure it from the other end to 5 meters and make a mark B. at this time, the distance between AB is 25% of the total length
How long is the bamboo pole

The length of bamboo pole is x M
Then 25% x = 5 + 5-x
The solution is x = 8
The bamboo pole is 8 meters long

If a + B − CC = a − B + CB = − a + B + Ca, then (a + b) (B + C) (c + a) ABC equals ()
A. 8B. 4C. 2D. 1

∵ a + B − CC = a − B + CB = − a + B + Ca, ∵ a + B − C + a − B + C − a + B + Ca + B + C = 1 = a + B − CC = a − B + CB = − a + B + Ca, ∵ 2A = B + C, 2C = a + B, 2b = a + C, ∵ (a + b) (B + C) (c + a) ABC = 2C × 2A × 2babc = 8, so select a

As shown in the picture, it is a triangular land. We plan to plant two different kinds of flowers and plants, a and B, on this triangular land
It is known that the length of EF on one side of the triangle is 160m and the height of EF on the other side is 50m. How to divide the land so that the total cost ratio of planting a and B is 2:3

What about the picture

The radius of circle O is 10cm, the chord PQ / / Mn, and PQ = 12cm, Mn = 16cm. Calculate the trapezoidal area with two parallel chords as the bottom

Make OA perpendicular to Mn and point a, OB perpendicular to PQ and point B
According to the vertical diameter theorem and Pythagorean theorem, OA = 6 and ob = 8 can be obtained
When Mn and PQ are on the same side of the circle center
AB=8-6=2
S=1/2(PQ+MN)*AB=28cm²
When Mn and PQ are on the opposite side of the circle center
AB=8+6=14
S=1/2(PQ+MN)*AB=196cm²

It is known that the square root of 2a-1 is ± 3, and the square of 3A + B is ± 4. The process of finding the square root of a + 2B