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All formulas of physics, including deformation formula
If it is the old version of Ohm's law of electricity and its deformation formula I = u / R, u = IR, r = u / I, the calculation formula of electric work (or consumed electric energy) w = uit = u2t / r = i2rt = PTW = 50R ／ 2500r / kW · h or 500imp ／ 5000imp / kW · h, w = w end of this month - end of last month, etc
The formula of buoyancy
Come on
Your answers are as follows:
The formula of buoyancy is: F = ρ VG (where ρ is the density of liquid, unit: kg / M & # 179;; V is the volume of liquid, unit: M & # 179;; G is the acceleration of gravity, unit: n / kg; generally, G is 10N / kg or 9.8n/kg.)
What are the formulas of eighth grade physics
Electricity:
Ohm's Law:
I=U/R
U=IR
R=U/I
Electric power:
Q=i^2Rt
Q=u^2/Rt
Q=UIT
w-i^2Rt
w=UIT
w=U^2/Rt
w=Pt
P=w/t
P=UI
P=u^2/R
p=I^2R
5 / 8 + 7 / 9 + 3 / 8 =, 25 / 18 -- 2 / 5 -- 3 / 5 =, 5 / 9 -- 5 / 12 + 4 / 9 =, 2 / 3 + 7 / 10 + 1 / 3 + 3 / 10 =, 8 / 9 -- (1 / 5 -- 1 / 9), 5 / 12 + 11 / 15 -- 6 / 15 + 7 / 12=
5/8+7/9+3/8
=5/8+3/8+7/9
=1+7/9
=1 and 7 / 9
25/18--2/5--3/5
=25/18-（2/5+3/5）
=25/18-1
=7/18
5/9--5/12+4/9
=5/9+4/9-5/12
=1-5/12
=7/12
2/3+7/10+1/3+3/10
=2/3+1/3+（7/10+3/10）
=1+1
=2
8/9--(1/5--1/9)
=8/9+1/9-1/5
=1-1/5
=4/5
5/12+11/15--6/15+7/12
=5/12+7/12+（11/15-6/15）
=1+1/3
=1 and 1 / 3
A necessary and sufficient condition for an image with function f (x) = 13ax3 + 12ax2-2ax + 2A + 1 to pass through four quadrants is ()
A. -43＜a＜-13B. -1＜a＜-12C. -65＜a＜-316D. -2＜a＜0
F ′ (x) = a (x-1) (x + 2). If a ＜ 0, then f ′ (x) ＜ 0 when x ＜ - 2 or X ＞ 1, and f ′ (x) ＞ 0 when - 2 ＜ x ＜ 1, then f (- 2) ＜ 0, and f (1) ＞ 0, ｜ − 65 ＜ a ＜− 316, so C
Seven out of eight, compared with eight out of nine
Minus seven eighths = - 1 + one eighth
And eight out of nine = - 1 + one out of nine
And 1 out of 8 > 1 out of 9
So minus seven eighths > minus eight ninths
The maximum value of function f (x) = 3sin (x + 10 degrees) + 5sin (x + 70 degrees)
Solution
x+70=x+10+60
f(x)=3sin(x+10)+5sin(x+10)*cos60+5*sin60*cos(x+10)
=(11/2)sin(x+10)+5*cos(x+10)3^0.5
=7 * sin (x + 10 + α) Tan α = (10 * 3 ^ 0.5) / 11 auxiliary angle formula
-1≤sin(x+10+α)≤1
f(x)max=7
The maximum value of the function f (x) is 7
A simple algorithm of 5 / 8 + 16 / 7 + 14 / 11
Complex algorithm can also, but there must be a process!
It seems that there is no easy way. In the end, it must be unified
5/8+16/7+14/11
=3+5/8+2/7+3/11
=3+5/8+1-5/7+3/11
=4-5/56+3/11
=4+(3*56-5*11)/(56*11)
=4+113/656
When x = 3, a quadratic function is known to have a maximum value of - 1, and the graph of the function intersects with the Y axis at (0, - 4)
Let y = a (x-3) 2-1, substituting point (0, - 4), we get - 4 = a (- 3) 2-1, a = - 13, y = - 13 (x-3) 2-1
Water is composed of hydrogen and oxygen. The mass ratio of hydrogen and oxygen is 1:8100 g. water contains several grams of hydrogen and oxygen
1+8=9
100 times 8 / 9 = 8 / 9 oxygen
100 times one in nine = one in nine hydrogen
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