It is known that the hypotenuse of a right triangle is 4.5 meters and a right side is 2 meters. What is the angle between them

It is known that the hypotenuse of a right triangle is 4.5 meters and a right side is 2 meters. What is the angle between them

It's very easy to calculate with Sina
Sina = opposite side of angle a divided by hypotenuse = 2 divided by 4.5 = 0.444
Sin26 = 0.4383711467890774, sin27 = 0.45399049973954675
Then 180-90-angle A is used to get the second angle
Originally there was a picture, but now I can't find the place to upload it

Is preparation a noun or a verb? What is its antonym

Preparation can be a noun (e.g. preparation) or a verb (e.g. are you ready?)

Solving triangles
The questions are as follows:
If (a + B + C) (B + C-A) = 3ABC and Sina = 2sinbcosc, then what triangle is △ ABC?
Please write down the judgment basis and process

I don't know if there is any mistake in the question
If (a + B + C) (B + C-A) = [3ABC] is right, I can't calculate it
If it is (a + B + C) (B + C-A) = [3bC], it is what I said upstairs
Well, if I had known it was 3b, I wouldn't have wasted so much time

English general past tense, past continuous tense and past perfect tense

The general past tense is expressed by the past tense, the verb be has two forms of was and were according to the person, the regular verb adds - D - or ed at the end of the word; other verbs refer to the irregular verb change table, which mainly indicates the action or situation at a certain time in the past

This paper briefly introduces the meaning and relationship of cognitive subject and cognitive object
Marxist Philosophy

Cognitive subject: human (sociality and practicality)
Cognitive object: transformation and cognitive object
Interrelation (the essence of cognition): transform, be transformed, reflect, be reflected

Ask the plural question
If Z1 and Z2 are conjugate complex numbers,
Then what graph does z1z2 + Z1 + Z2 = 0 represent

Let Z1 = x + Yi, then Z2 = x-yi
z1z2+z1+z2
=x^2+y^2+2x=0
x^2+y^2+2x=0
(x+1)^2+y^2=1
Is a circle with (- 1,0) as the center and radius 1

What is the meaning of the modernization of law?

Law

My favorite sport
To 120-200 words, not more, not less
It's best to write about table tennis, badminton, or tennis
Yes, it will
What the man on the fourth floor said is really mysterious=

My Favourite Sport
Like others,I like sports.I usually do sports in my spare time.and as a result,it has done good to me.I am strong and in good spirits.But of all the sports,badminton is my favorite.It 's very interesting and I can play it at anytime anywhere, and I don't feel very tired after playing.Playing badminton for one hour or two is my daily exercise.Sometimes I do it with my classmates,and sometimes just with my father.He is a badminton lover too.He often says that badminton can not only build up one's body,but also develop one's reaction ability.I am for it.Friends ,what about you?Do you like badminton either?

As shown in the figure, after a cylinder is cut off 5cm, the surface area of the cylinder is reduced by 31.4cm2

Bottom circumference: 31.4 △ 5 = 6.28 (CM), bottom radius: 6.28 △ 3.14 △ 2 = 1 (CM), two bottom areas: 3.14 × 12 × 2 = 6.28 (cm 2), side area: 6.28 × 20 = 125.6 (cm 2), surface area: 125.6 + 6.28 = 131.88 (cm 2). Answer: the surface area of the original cylinder is 131.88 cm 2

The natural number a = B-1, the least common multiple of a and B is (), and the greatest common factor is ()

The natural number a = B-1, the least common multiple of a and B is (AB), and the greatest common factor is (1)