Let F 1 and F 2 be the left and right focus of hyperbola x ^ / A ^ - y ^ / b ^ = 1 respectively, and make a point a on the hyperbola so that the angle f 1af = 90 degrees and / AF1 / = 3 / af2 / Hyperbola e e =?

Let F 1 and F 2 be the left and right focus of hyperbola x ^ / A ^ - y ^ / b ^ = 1 respectively, and make a point a on the hyperbola so that the angle f 1af = 90 degrees and / AF1 / = 3 / af2 / Hyperbola e e =?

Let | AF1 | = 3q, then | af2 | = Q. from Pythagorean theorem, | F1F2 | = q √ 10 = 2c, that is, C = q √ (10) / 2
The definition of hyperbola is a = (| AF1 | - | af2 |) / 2 = Q
So e = C / a = √ (10) / 2

It is known that the two focal points of the hyperbola x ^ 2 / 9-y ^ 2 = 1 are F1, F2, a is a point on the hyperbola, and | AF1 | = 5, then | af2 | = what

For hyperbola, there are:
||AF1 | - | af2 | = 2A = 6, because | AF1 | = 5, then:
|Af2 | = 11 or af2 | = - 1
Then: | af2 | = 11

Let F1 and F2 be the two focal points of hyperbola x ^ 2-4y ^ 2 + 16 = 0, and the straight line passing through point F2 intersects the hyperbola at two points a and B, then AF1 + bf1-ab =?

Hyperbola x ^ 2-4y ^ 2 + 16 = 0
Hyperbolic standard equation: y ^ 2 / 4-x ^ 2 / 16 = 0
a=2,b=4
The straight line intersection hyperbola passing through point F2 is at two points a and B
AF1-AF2=2a,BF1-BF2=2a,AB=AF2+BF2
AF1+BF1—AB=(AF1-AF2)+(BF1-BF2)
=4a
=4

Why is the formula of volume v = mass m / density ρ instead of V = mass MX density ρ
Isn't density ρ = mass m / volume V? Then why isn't the volume formula v = MP

Because from a mathematical point of view, ρ = m / v
Multiply both sides of the equation by V
We get ρ v = M
Divide both sides by ρ at the same time
We get v = m / ρ
Are you careless when you move items

If the ground side of a quadrilateral prism is 1 cm long, what is its surface area

It is a square with a side length of 1cm and a body diagonal of 2cm
According to Pythagorean theorem, 2 ^ 2 = 1 ^ 2 + 1 ^ 2 + H ^ 2
The solution is h = root 2
Then the surface area s = 1 + 1 + 4 * 1 * radical 2 = 2 + 4 radical 2

Solution set of all points on the coordinate axis of rectangular coordinate system
It's not a solution set, it's a set. Another question: the set of all points of quadratic function y = x & sup2; + 2x?

First question: {(x, y) | x belongs to R, y belongs to R}
Second question: {(x, y) | x belongs to R, y = x & sup2; + 2x}

Build a cement road with a width of 3.6 meters and a thickness of 20 cm. If 7.2 cubic meters of concrete is mixed, how many meters can it be paved?

20 cm = 0.2 m, 7.2 △ 3.6 × 0.2, = 7.2 △ 0.72, = 10 m; a: it can be paved for 10 m

Let a > b > C > 0, then the minimum value of 2A2 + 1ab + 1a (a − b) - 10ac + 25c2 is______ ．

∵ a > b > C > 0, ∵ 2A2 + 1ab + 1a (a − b) - 10ac + 25c2 = A2 + 1B (a − b) + (a − 5C) 2 ≥ A2 + 1 (B + a − B2) 2 + (a − 5C) 2 = A2 + 4a2 + (a-5c) 2 ≥ 2A2 · 4a2 + 0 = 4

Conversion relations among micron, millimeter and nanometer (6)
There are six relationships among them

1 mm = 1000 micron, 1 micron = 1000 nanometers, 1 millimeter = 1000000 nanometers. I only know these three, sorry ~ ~ but I really don't know where there are six, please forgive me ~ ~ thank you

There are two solid balls a and B. the mass of ball a is four times that of ball B, and the volume of ball a is twice that of ball B. then the density of ball a is twice that of ball B

4/2=2