ศัพท์คณิตศาสตร์ระดับ ม.ต้น

1. Mathematics Vocabulary
Miscellaneous Symbol
Symbol Reading Thai
= is equal to
 is not equal to
 is approximately equal to
 Is equivalence to
> is greater than
 is greater than or equal to
< is less than
 is less than or equal to
infinity
+ plus
- minus
 Multiply
 divide
How to Read Mathematical Notations?
Notations Reading Thai
-3 Negative 3
an
 a raised to the power of n
 a raised to the n-th power
 a raised by the exponent
of n
 a to the n
34

2. Notations Reading Thai
a2
a3
(-2)6
|4|
|-5|
a + b
a – b
a  b, ab, ab
a  b, a/b,
a : b
2 + 7 = 9 2 plus 7 equal to 9
2 plus 7 equal 9
2 plus 7 is 9
7 – 15 = -8
4 x 12 = 48
12  (-2) = -6
1 over 2,
Half
1 over 4,
Quarter
3 over 4,
3 Quarters
1 over 3
One-third
5 over 6
2.45 Two point four five

3. Notations Reading Thai
a : b The ratio of a and b
3 : 5
√ Square root of a
√
Type of Numbers
Type Example Thai
Natural Numbers
Counting Numbers
Integer Numbers
Positive Integer
Numbers
Negative Integer
Numbers
Odd Numbers
Even Numbers
Prime Numbers
Whole Numbers
Rational Numbers
Irrational Numbers

4. Type Example Thai
Fraction
Numerator
Denominator
Improper Fraction
Proper Fraction
Reduce a Fraction
Decimal
Repeating decimal
Real Numbers
GCF: Greatest Common Factor
LCM: Least Common Multiple

5. Type Example Thai
Ratio
Antecedent
consequent
Proportion
Remainder
Quotient
Sum
Geometric Figures
Point Line, Straight line
Line segment Ray
Angle Obtuse angle
Right angle Acute angle
Reflex angle Flat angle, Straight angle

6. Parallel line Alternate angle
Alternate exterior angle
Alternate interior angle
Vertical angle
Interior angle
Exterior angle
Figure
Triangle
 Equilateral Triangle  Scalene Triangle
 Right Triangle  Obtuse Triangle
 Acute Triangle  Isosceles Triangle

7. Quadrilateral
 Rhombus  Trapezoid
 Isosceles Trapezoid  Square
 Parallelogram  Trapezium
 Rectangle  Kite
Polygon
Pentagon hexagon

8. Heptagon Octagon
Nonagon Decagon
Hendecagon Dodecagon
Circle Radius
Center
Diameter
Circumference
Perimeter
Ellipse

9. Solid Figure
 Cube
 Cuboid
 Cone

10.  Pyramid
 Prism

11.  Cylinder
 Sphere
 Ellipsoid

12.  Tetrahedron  Pentahedron
 Hexahedron  Heptahedron
 Octahedron  Polyhedron
Chart
Bar chart

13. Pictogram
Pie-chart

14. Solving equation
Example 1 Solve the equation 3x−4=2.
first step we add 4 both sides then we have
3x−4+4=2+4
3x=6
second step we divide both sides by 3.
3x3=63
x=2
Example 2 Solve the equation 9(x+1)=2(3x+8).
Step 1 we expand each side
9x+9=6x+16
Step 2 subtract 6x from both sides.
9x+9−6x=6x+16−6x
Step 3 subtract 9 from both sides.
3x+9−9=16−9
3x=7
Step 4 divide both sides by 3.
3x3=73
x=73