# 英语中数学符号表达

Pronunciation of Mathematical Expressions The pronunciations of the most common mathematical expressions are given in the list below. In general, the shortest versions are preferred (unless greater precision is necessary). 1、Logic

?
?

there Exists for All / Any p implies q / if p, then q p if and only if (iff) q / p is equivalent to q / p and q are equivalent

p?q
p?q

2、Sets
x? A
x? A
A? B A? B

x belongs to A / x is an element (or a member) of A x does not belong to A / x is not an element (or a member) of A A is contained in B / A is a subset of B A contains B / B is a subset of A A cap B / A meet B / A intersection B A cup B / A join B / A union B A minus B / the difference between A and B A cross B / the Cartesian product of A and B

A? B A? B

A\ B
A? B

3、Real numbers
x ?1
x ?1 x ?1
xy

x plus one x minus one x plus or minus one xy / x multiplied by y x minus y, x plus y

( x ? y)(x ? y)

x y

x over y / x on y the equals sign x equals 5 / x is equal to 5 x (is) not equal to 5 x is equivalent to (or identical with) y x is not equivalent to (or identical with) y x is greater than y x is greater than or equal to y x is less than y x is less than or equal to y zero is less than x is less than 1 zero is less than or equal to x is less than or equal to 1 mod x / modulus x / absolute value of x x squared / x (raised) to the power 2 x cubed x to the fourth / x to the power four x to the nth / x to the power n x to the (power) minus n (square) root x / the square root of x cube root (of) x fourth root (of) x nth root (of) x x plus y all squared x over y all squared n factorial

x?5 x?5
x? y

x? y
x? y

x? y
x? y

x? y

0 ? x ?1 0 ? x ?1

x
x2 x3

x4 xn
x ?n

x
3

x x x

4

n

( x ? y) 2
? ? ? ? x? ? y? ?
2

n!

? x
x

x hat x bar x tilde xi / x subscript i / x suffix i / x sub i xi / x superscript i / x superfix i / x super i
i

~ x

xi
xi

?a
i ?1

n

the sum from i equals one to n ai / the sum as i runs from 1 to n of the ai

4、Linear algebra

x

the norm (or modulus) of x OA / vector OA OA / the length of the segment OA A transpose / the transpose of A A inverse / the inverse of A

OA
OA
AT A ?1

5、Functions
f (x) f : S ?T

f x / f of x / the function f of x a function f from S to T x maps to y / x is sent (or mapped) to y f prime x / f dash x / the (first) derivative of f with respect to x f double–prime x / f double–dash x / the second derivative of f with respect to x

x? y
f ?(x)

f ??(x) f ???(x)

f triple–prime x / f triple–dash x / the third derivative of f with respect to x f four x / the fourth derivative of f with respect to x partial F on partial x / partial differential F on x

f ( 4) ( x)
?F ?x

?f ?x1

the partial (derivative) of f with respect to x1

?2 f 2 ?x1

the second partial (derivative) of f with respect to x1

?

?

0

the integral from zero to infinity the limit as x approaches zero the limit as x approaches zero from above the limit as x approaches zero from below log y to the base e/ log to the base e of y / natural log (of) y log y to the base e / log to the base e of y / natural log (of) y

lim
x?0

x ? ?0

lim lim

x ? ?0

loge y
ln y

Individual mathematicians often have their own way of pronouncing mathematical expressions and in many cases there is no generally accepted “correct” pronunciation. Distinctions made in writing are often not made explicit in speech; thus the sounds fx may be interpreted as any of: fx,

f ( x), f x , FX , FX , FX . The difference is usually

made clear by the context; it is only when confusion may occur, or where he/she wishes to emphasize the point, that the mathematician will use the longer forms: f multiplied by x, the function f of x, f subscript x, line FX, the length of the segment FX, vector FX. Similarly, a mathematician is unlikely to make any distinction in speech (except sometimes a difference in intonation or length of pauses) between pairs such as the following:
x ? ( y ? z ) and ( x ? y ) ? z

ax ? b
a n ?1

and and

ax? b
a n?1

6、其它数学符号和公式例子 4/5 0.025 38.49 2%
52

four fifths / 4 on 5 zero point zero two five thirty-eight point four nine two per cent the second power of five / five to the power two the square root of x six times the seventh power of ten plus ; positive minus ; negative multiplied by ; times divided by is equal to ; equals round brackets ; parentheses (parenthesis) imaginary unit factorial a sine of x arc sine of x the product of the terms indicated the sum of the terms indicated b prime b second prime

x
6 ? 107

?
?

?; /

= () i; j
a!
sin x arcsin x
?

b? b ??

b2
bm ?

b sub two b second prime sub m the first derivative of y with respect to x the second derivative of y with respect to x integral between limits a and b x approaches to infinity a plus b is equal to c a minus b equals c s equals v multiplied by t v equals s divided by t a plus b minus c multiplied by d, all divided by e equals f C over R equals G divided by the sum of one and H times G

dy / dx

d 2 y / dx2

?

b

a

x ??
a?b ? c
a?b ? c

s ? vt
v ? s/t
(a ? b ? c ? d ) / e ? f C / R ? G /(1 ? GH )