She teaches us Chinese and English translation

She teaches us Chinese and English translation

She teachs us Chinese

Given a vector = (2,2), (a vector Λ, B vector = π / 4, find the coordinates of the absolute value of B vector

"Under absolute value [a vector + B vector] = two fifths of the change sign 5", the square of both sides of a vector XB vector = - 3 / 5, namely cosxcosy + sinxsiny = - 3 / 5
Cos (X-Y) = - 3 / 5

In the triangle ABC, if AB = AC, P is the moving point on BC and not the midpoint of BC, we prove that ab square AP square = BP * PC

Let ad ⊥ BC be crossed with D, AB & sup2; = BD & sup2; + AD & sup2; (1) AP & sup2; = PD & sup2; + AD & sup2; (2) (1) - (2) get: ab & sup2; - AP & sup2; = BD & sup2; - Pd & sup2;, ≁ AB & sup2; - AP & sup2; = (BD + PD) (bd-pd), ∵ AB = AC, ≁ D is the midpoint of BC, ≁ BD + PD = PC, B

10x ^ 2-21xy + 2Y ^ 2 factorization factor
The more detailed, the better. Multiply by cross

A:
10x^2-21xy+2y^2
The cross multiplication is as follows
10x -y
*
x -2y
-2y*10x-xy=-21xy
So:
10x^2-21xy+2y^2=(10x-y)(x-2y)

ρ = root sign 2Sin (θ + π / 4) is transformed into rectangular coordinate equation

ρ = root sign 2Sin (θ + π / 4)
ρ=√2（sinθcosπ/4+cosθsinπ/4)
ρ =sinθ+cosθ
Two times ρ:
ρ²=ρsinθ+ρcosθ
∵ρ²=x²+y²,ρsinθ=y,ρcosθ=x
∴x²+y²=y+x
The rectangular coordinate equation
(x-1/2)²+(y-1/2)²=1/2

In the triangle ABC, the angle ACB is 90 degrees, the angle CD is high, and the angle a is 30 degrees

In the triangle ABC, the angle ACB = 90 degrees, the angle a = 30 degrees, so the angle B = 60 degrees and the angle CD = 90 degrees. In the right triangle ABC, the angle BC = 2 / 1ab (the right side opposite 30 degrees is equal to half of the hypotenuse) is the same as in the right triangle ADB, the angle bad = 30 degrees or BD = 2 / 1BC

How many meters per second is 2.1km per hour

Given that f (x) = 1 + logx2g (x) = 2logx2, try to compare the size of F (x) and G (x)

The side length of a square is ACM. Increase its side length by 2cm. What is the perimeter of the new square?

The side length of a square is ACM. Increase its side length by 2cm, and the perimeter of the new square is 4 (a + 2) cm

When sinusoidal alternating current passes through resistance R, inductance L and capacitance C, what is the direction of voltage and current formed on it?

If you connect the resistance in series in the circuit, the direction of voltage and current will be the same as that when it is not added. Only the current will be reduced, and the resistance will have limited current effect. If you connect the inductance in series in the circuit, it will produce inductive reactance, which will oscillate with alternating current, and the direction of instantaneous current will be opposite. If you connect the capacitor in series in the circuit, it will produce capacitive reactance, and the current will advance 90 degrees, and the direction of voltage and current will be opposite at the moment of discharge