The function f (x) = Tan (x + φ) is odd if and only if φ = k π K ∈ Z why is the false proposition TVT

Its necessary and sufficient condition is that φ = k π / 2 (K ∈ z), f (x) = Cotx, and it is also an odd function

If f (x) is an odd function, and if x > 0, f (x) = x2 + SiNx, then if x ∈ R, f (x)=
Just the answer

f(-x)=-f(x)=-x^2-sinx=-(-x)^2+sin(-x)
We get f (x) = - x ^ 2 + SiNx (x0)

What are the plurals of live and life
》》》

Live is a verb, there is no plural, only the third person singular lives, and the plural form of life is the same as the simple three of live

How to draw parallelogram with oblique binomial drawing method

The angle between axes xoz of oblique second surveying is 90 degrees, that is to say, if you draw in the axonometric plane x1o1z1, you will get a figure reflecting the solid shape. Therefore, you can draw the parallelogram in this axonometric plane

A word for a large number

Countless
innumerable
Unlimited
many
quite a lot
A lot

As shown in the figure, BD and CE are the two heights of triangle ABC, and m and N are the midpoint of BC and de respectively

Connecting DM, EM, ∵ m is the midpoint of BC, BD and CE are the two heights of △ ABC, ∵ EM = 12bc, DM = 12bc, ∵ EM = DM, ∵ n is the midpoint of De, ∵ Mn divides de vertically

English conjunctions in Grade 6
gate,her,to,little,up,that,dinner,her,pick,going,and,have,kind,is,take,then,girl,is,to,school,at,father,the
(girl, is's Chinese is girl's)

The sixth grade makes such a long sentence

The third denominator of thirteen can be reduced to one-third after adding () to the numerator at the same time?

Set to X
x+3／x﹢13=1／3
Solve the equation: x = 2
The answer is 2

What are the differences between modifying countable nouns and uncountable nouns?

First of all, it is necessary to modify countable or uncountable nouns, not singular or plural nouns. Countable nouns have plural forms, while uncountable nouns have no plural forms
A large deal of, a plenty of and a good supply of modify uncountable nouns in most cases, such as a plenty of water, a deal of time, but they can also modify countable nouns, such as a plenty of men
In most cases, a quantity of modifies countable nouns, such as a quantity of boxes, but it can also modify uncountable nouns, such as a quantity of milk
The same as above
1、 Words that can only modify countable nouns are:
Many, many a (n), a good / great many, a (great / large) number of, scores of, dozens of, etc
Scores of people went there in the first few days after its opening.
A lot of people went there in the first few days after opening
I have been there dozens of times.
I have been there many times
There’re a number of students reading English in the classroom.
There are many students reading English in the classroom
Many a student has (= many students have) visited the Great Wall
Many students have visited the Great Wall
In winter,a good many animals sleep under the snow.
Many animals hibernate under the snow in winter
Note: the plural noun modified by "many" is preceded by a finite determiner, and "many" is followed by "of" Many of them
A great many(of the) graduates have found jobs.
Many of the graduates have found jobs
2、 Words that can only modify uncountable nouns are:
Many, a great deal of, a great / large amount of, etc
Is there much water in the bucket?
Is there a lot of water in the bucket?
He always has a great amount of work to do.
He always has a lot of work to do
3、 Words that can modify both countable and uncountable nouns are as follows:
A lot of, lots of, plenty of, a great / large quantity of, and quantities of
There is still lots of snow in the garden.
There is still a lot of snow in the garden
There is plenty of rain here.
There is a lot of rain here
A great quantity of flowers was placed in the hall.
There are many flowers in the hall
There are large quantities of food in the cupboard.
There is a lot of food in the cupboard
Among all these words, many and much are the most commonly used. They can be used in affirmative sentences, interrogative sentences and negative sentences
Are there many people in the street?
Are there many people in the street?
There isn’t much time left.
There is not much time left
Other words are used in affirmative sentences, such as lots of, a lot of or plenty of in daily conversation, a great many, a (large) number of, a great deal of, scores of or dots of in formal style
The number of the people who lost their homes reached as many as 250,000.
As many as 250000 people are homeless
There is too much work to do.
There is too much work to do

a^3-a^2-4a+4=0

a^2(a-1)-4(a-1)=0
(a-1)(a^2-4)=0
(a-1)(a+2)(a-2)=0
a=1,a=-2,a=2

The function f (x) = Tan (x + φ) is odd if and only if φ = k π K ∈ Z why is the false proposition TVT