In an acute triangle, the range of the largest angle a is a.0 degrees

In an acute triangle, the range of the largest angle a is a.0 degrees

D
If the maximum is less than 60 degrees, the sum of internal angles is less than 180 degrees
If the largest is greater than or equal to 90 degrees, it is not an acute triangle

If the sum of all angles in the figure is equal to 180 degrees, calculate the degree of AOB

As shown in the figure, let ∠ 1 = ∠ 2 = ∠ 3 = x, ∫ AOC + ∠ AOD + ∠ AOB + ∠ cod + ∠ cob + ∠ DOB = 180 °, x + 2x + 3x + X + 2x + x = 180 °, x = 18 ° and ∠ AOB = 3x = 54 °

As shown in the figure, given the acute angle α, find an angle so that it is equal to 180 ° - α

By extending either side of it reversely, we get a new angle: 180-a

Given that point a is on the parabola y ^ 2 = 4x, a straight line AP passing through point a as circle C: (x-1) ^ 2 + y ^ 2 = 1, AQ intersects Y-axis at m, N, P, Q, which are tangent points
1. If a (4,4), find the PQ linear equation
2. If the vector am multiplies the vector an = - 2, the coordinate of point a is obtained

(1) Because C (1,0), P (4,4), the center of the circle with CP as diameter is (5 / 2,2), and the radius is 5 / 2, so the equation of circle is (X-5 / 2) ^ 2 + (Y-2) ^ 2 = 25 / 4, and the equation of PQ is 3x + 4y-4 = 0 by making a difference from the given equation of circle

If (M + n) ² = 4x & #178; + 12x + B, then B is

How to match this question!
4x²+12x+b
=(2x+3)^2
∴ b=3^2=9

The edge length of cube abcd-a1b1c1d1 is 2, e is the midpoint of AB, and the distance from B to plane a1ec is calculated
The answer is six-thirds root

Methods: the distance from point B to plane a1ec can be calculated from the volume of triangular pyramid a-bce = the volume of triangular pyramid b-a1ec. Because A1A ⊥ plane BCE, A1A is the volume of high triangular pyramid a-bce of triangular pyramid a-bce = (1 / 3) s △ BCE · A1A = (1 / 3) · (1 / 2) · be · BC · A1A = (1 / 2) · 1 · 2 · 2 = 2 / 3

First simplify, then evaluate, x plus one-half minus x plus the square of two-thirds of x plus 2x plus 1 divided by x minus the square of one-half of x minus 1
Medium x = 2

(1-x) / (x + 2) + (X & # 178; + 2x + 1) / 2 ÷ (X & # 178; - 1) / X-1 = (1-x) / (x + 2) + (x + 1) / # 178; × (x-1) / (x + 1) (x-1) = (1-x) / (x + 2) + (x + 1) = [1-x + (x + 2) (x + 1)] / (x + 2) = (X & # 178; + X + 3) / (x + 2) when x = 2: (2 & # 178; + 2 + 3) / (2 + 2) = 9 / 4

Given that 1 / A + 1 / b = 5, what is 2A + 2b-7ab / a-3ab + B equal to

1 of a + 1 of B = 5, a + B = 5ab
2a+2b-7ab=10ab-7ab=3ab
a-3ab+b=5ab-3ab=2ab
So the result is two-thirds

Guess idioms according to the formula: 1. 9 + 1 = 1; 2. 17 △ 5 = 3.4; 3. 5 + 10 = 15; 4. 100:100
Nine to one, no three, no four, no five

Barbie dolls

Is a parallelogram, known on both sides are 6 cm and 10 cm, one of the bottom of the height is 8 cm, the area of this parallelogram is () square centimeter
A. 80B. 60C. 48

6 × 8 = 48 (square centimeter); answer: the area of this parallelogram is 48 square centimeter