On X equation (2a.9 ^ x) + (4a.3 ^ x) + A-8 = 0, if there is a solution on X ∈ [- 1,1], then a ∈_________

On X equation (2a.9 ^ x) + (4a.3 ^ x) + A-8 = 0, if there is a solution on X ∈ [- 1,1], then a ∈_________

Let 3 ^ x = m (M > 0), then when x ∈ [- 1,1], 1 / 3

The solution of the acute equation (x + 1) / (x + 2) + (x + 8) / (x + 9) = (x + 2) / (x + 3) + (x + 7) / (x + 8) is______

(x + 1) (x + 9) (x + 3) (x + 8) + (x + 8) (x + 2) (x + 3) (x + 8) = (x + 2) (x + 2) (x + 8) (x + 9) + (x + 7) (x + 2) (x + 9) (x + 3) merge congeners (x + 1) (x + 9) (x + 3) (x + 8) - (x + 2) (x + 2) (x + 8) (x + 9) = - (x + 8) (x + 2) (x + 3) (x + 8) + (x + 7) (x + 2) (x + 9) (x + 3) (x +

It is known that in a right triangle, the length of two right angles is a, B, the hypotenuse is C, and the height of the hypotenuse is h
1 / 2 of a + 1 / 2 of B = 1 / 2 of H

Write the comparative, superlative and antonyms of the following adjectives
short ,long ,heavy ,happy ,nice ,interesting ,big ,thin ,good ,many ,bad ,little

short shorter shortest longlong longer longest shortheavy heavier heaviest lighthappy happier happiest sadnice nicer nicest badinteresting more interesting the most interesting boringbig bigger bigges...

In triangle ABC, if you solve a triangle according to the following conditions, there are two solutions
b=10,A=45°B=70°
a=60 c=48 B=100°
a=7 b=5 A=80°
a=14 b=16 A=45°

a=14,b=16,A=45
a²=b²+c²-2bccosA
c²-(2bcosA)c+b²-a²=0
c²-16√2c+60=0
The discriminant is greater than 0, so there are two solutions
And C1 + C2 = 16 √ 2 > 0
c1c2=60>0
So both solutions are greater than 0
So there are two solutions
So it's the last group

Make five sentences with the original form of should + verb and five sentences with the like + verb ing

I should run with you.
I should write with you.
I should eat with you.
I should walk with you.
I should drink with you.
I like running with you.
I like writing with you.
I like eating with you.
I like walking with you.
I like drinking with you.

Wei Wei's "my teacher" as for the summer vacation for a child who likes his teacher, and how long! In the long meaning and expression of the role
In retrospect, I still feel that this is one of the treasures in my memory. The meaning and expression of the treasure in my memory

Meaning is: to describe the degree of great, refers to the time
I like the teacher, like to be with the teacher, expressing a child's deep miss for the teacher
Meaning: treasure, precious
Expression means: such a thing is still fresh in my mind, which is of great help to me, so it is a treasure

Complex number and angle in MATLAB
Complex number has coordinate formula and module, phase angle formula (polar coordinate formula), how to express phase angle formula (polar coordinate formula) in MATLAB? In addition, can angle be expressed directly by degree

When 45 degrees, the real axis is 1 and the imaginary axis is I, then
>> angle(1+i)*180/pi
ans = 45
As you can see, angle calculates radian, which is multiplied by 180 / PI and converted into angle
>> angle(i)*180/pi
ans = 90
At right angles, the real axis is 0
>> abs(1+i)
ans = 1.4142
4142 is root 2, module

There was a pile of peaches. The first monkey took half of the peaches and half of them. The second monkey took the remaining half and half of them. The third monkey took the last half and half of them. The peaches just ran out. Q: how many peaches were there?

The third monkey took away the last one peach, because it was impossible to leave half a peach, so it was one peach; the second monkey took two peaches, because the second monkey took three peaches, it took half and half, so it was two peaches; the first monkey took four peaches, because the second monkey took only three peaches, The first monkey has three and a half and a half, so it's four peaches
1 + 2 + 4 = 7 peaches A: there were 7 peaches in this pile

The usage difference between sports and Sport
Do sports or do sports? What are the requirements for their case?

Adjectives:
sports
adj.
About sports
sport
n.
Sports, games
Noun:
sport
n.
Entertainment, recreation, games
Sports, sports meeting
Funny thing, joke, joke, plaything, laughing stock, object of ridicule
[mouth] people with sportsmanship, athletes, likable people, broad-minded people, kind-hearted people, courageous people
Gambler, wine lover, enjoyment lover, beautiful and fashionable person
Mutation; budding; abnormal human
So it should be do sport. There is no special requirement for case