Solution equation: (2x-1) ^ 2-3 (2x-1) - 18 = 0

Solution equation: (2x-1) ^ 2-3 (2x-1) - 18 = 0

(2x-1)^2-3(2x-1)-18=0
(2x-1+3)(2x-1-6)=0
（2x+2）（2x-7)=0
x=-1,x=7/2

Solve the equation. 2x + 40% x = 7.2

2X+40％X=7.2
2.4x=7.2
x=7.2÷2.4
x=3

1/1*3+1/3*5+1/5*7+… +1 / 97 * 99 law finding calculation

If | FA | = 2 | FB |, then k = ()
A. 13B. 23C. 23D. 223

The parabola C: y2 = 8x is l: x = - 2 straight line, y = K (x + 2) (K \\\| = 2 124124 = 2 | FB |, then 124| = 2 124; am = 2 124\| BN |, point B is the midpoint of AP, connecting ob, then | ob \124; = 12 | AF |, | ||||||||124;|||124;\124;\|||\124;therefore, D is selected because − 01 − (− 2) = 223

How cuboid and cylinder calculate volume

Cuboid volume = length × width × height cylinder volume = bottom area × height

How to calculate 34 plus 99 times 34 with the law of multiplicative distribution

This question must have been asked by primary school students. The key step has been omitted in the upstairs answer
34+99×34
=34×1+99×34
=34×（1+99）
=34×100
=3400

Let f (x) = lnx-kx + 1. (1) find the monotone interval of F (x); (2) if f (x) ≤ 0, it holds
Try to determine the value range of real number K

(1) The definition field of function f (x) is (0, + ∞), then f ′ (x) = 1 / X &; K (1) when k ≤ 0, f ′ (x) = 1 / X &; K ＞ 0, f (x) is an increasing function on (0, + ∞). ② when k ＞ 0, if x ∈ (0,1 / k), f ′ (x) = 1 / X &; K ＞ 0, if x ∈ (1 / K, + ∞), f ′ (x) = (1 / x) = (0,1 / K, + ∞)

Calculation: the density of oxygen in a steel cylinder is 8kg / M & sup3;, 1 / 4 of which is used for one welding

The mass of oxygen in the cylinder is reduced by "1 / 4", and the mass of remaining oxygen is 3 / 4 of the original mass, that is M2 = (3 / 4) M1;
The volume of oxygen in the cylinder remains unchanged, that is, V2 = v1
Then ρ 1 / ρ 2 = (M1 / V1) / (m2 / V2) = (M1 / m2) / (V2 / V1) = 4 / 3
ρ2=3/4 ρ1=3/4x8㎏/m³=6㎏/m³

For example: A and B are natural numbers. How to define a △ B = a △ 2 + B △ 2 and calculate 24 △ 8

24△8
=24÷2+8÷2
=12+4
=16
Hope to help you~~~~

Now there is another kind of 3-cassette with 3-length, 2-width and 1-height. How many packaging methods are there? Which one is more economical?

There are three packaging methods:
Type 1: three boxes stacked (bottom stacked): 3 * 2 * 2 + 3 * 1 * 3 * 2 + 2 * 1 * 3 * 2 = 42
Or 3 * 3 * 2 + 3 * 2 * 2 + 2 * 3 * 2 = 42 (the most economical wrapping paper)
Type 2. Front and back connected packaging: 3 * 6 * 2 + 3 * 1 * 2 + 6 * 1 * 2 = 54
Type 3. Left and right connected packaging: 9 * 2 * 2 + 2 * 1 * 2 + 9 * 1 * 2 = 58