你能用英语把这个等式（equation）读出来吗？
被难倒了吧！
数学符号
Mathematical symbols
01
+: plus 加号；正号
“1+1”读作：one plus one
02
－: minus; negative 减号；负号
“2-1”读作：two minus one
“-3”读作：minus three或negative three
“2-(-3)”读作：two minus negative three
03
±: plus-minus sign 正负号
“±1” 读作：plus or minus one
04
×: multiplied by ; times 乘号
“2×3” 读作：two multiplied by three 或 two times three
05
÷: divided by 除号
“4÷2”读作：four divided by two
06
=: equals; is equal to 等于号
“1+1=2”读作：One plus one equals two.
或 One plus one is equal to two.
07
≠: is not equal to 不等于号
“a≠b”读作：a is not equal to b
08
≌: congruent to 全等（两个图形形状相同、大小相等）
“△ABC≌△DEF”读作：Triangle ABC is congruent to Triangle DEF.
09
≈: approximately equal to 约等于号
“3×3≈10” 读作：Three multiplied by three is approximately equal to ten.
10
<: is less than 小于号
“1<2”读作 One is less than two.
11
>: is greater than 大于号
“2>1”读作：Two is greater than one.
12
≮: is not less than 不小于号
“3≮2”读作：Three is not less than two.
13
≯: is not greater than 不大于号
“2≯4” 读作：Two is not greater than four.
14
≤: is less than or equal to 小于或等于号
“2≤3”读作：Two is less than or equal to three.
15
≥: is greater than or equal to 大于或等于号
“5≥4”读作：Five is greater than or equal to four.
16
%: percent 百分之……
“10%”读作：ten percent
17
‰ : per mill ; per thousand 千分之……
“10‰”读作：ten per thousand
18
∞: infinity 无限大号
“－∞” 读作：negative infinity
19
∝: varies as 与...成比例
“X∝Y”读作：X varies as Y
20
√￣: square root 平方根
“√￣16=4”读作：The square root of sixteen is four.
21
3√￣: cube root 立方根
“3√￣27=3”读作：The cube root of 27 is 3.
22
∵: since; because 因为
“∵1+1=2”读作：because one plus one equals two
23
∴: hence; therefore 所以
“∴1<2”读作：hence one is less than two
24
∠: angle 角
“∠A”读作：angle A
“∠A +∠B+∠C=180°”
读作：The measure of angle A plus angle B plus angle C equals 180 degrees.
25
⌒: semicircle 半圆
“⌒AB”读作：semicircle AB
26
⊙: circle 圆
“⊙A”读作：circle A
27
○: circumference 圆周
“○=π×d”读作：Pi multiplied by d equals circumference.
28
π: pi constant 圆周率
“π×d”读作：pi multiplied by d
29
△: triangle 三角形
“△ABC”读作：triangle ABC
What is the area of triangle ABC? 求三角形ABC的面积。
30
⊥: perpendicular to 垂直于
“A⊥B”读作：A is perpendicular to B.
31
//: parallel to 平行于
Line AB is parallel to line CD.
32
∪: union of 并，合集
“A∪B”读作：the union of A and B
33
∩: intersection of 交，通集
“A∩B”读作：The intersection of A and B
34
∫: the integral of ……的积分
“∫x”读作：the integral of x
35
∑: summation of 总和
“∑x”读作：the summation of x
36
equation 方程式、等式
“y = kx” 读作：
Y varies as x.
K is "the constant of variation.
y与x成正比（y是x的正比函数），k是常数。
“y = k/x”读作：
Y varies inversely as x.
y与x成反比例（y是x的反比例函数）。