Power Point Presentation on Introduction of Trigonometry By:- Kumar Prashant Dwivedi M.sc(Physics), B.Ed.
Transcript
1. Power Point Presentation on Introduction of Trigonometry
By:- Kumar Prashant Dwivedi M.sc(Physics), B.Ed.
2. Level:- 10th Subject:- maths Chapter:- Introduction of
Trigonometry No. of period required:- 10
3. Lets take some examples from our surroundings where right
triangle can be imagined to form:- If a student is looking at the
top of the tower , a right triangle can be imagined to be made
4. Half Slice of bread can be imagined to be made a right
triangle
5. In all the situation distances or heights can be found by
using some mathematical techniques which comes under a branch of
mathematics called trigonometry. Trigonometry is derived from Greek
words Tri + gon + metron (three) (sides) (measure) In fact
Trigonometry is the study of relation between the sides and angles
of a triangle.
6. Historical Background The history of trigonometry dates back
to the early age of Egypt and Babylon. Angles were then measured in
degree. It was then advanced by the Greek astronomer Hipperchus in
the second century of B.C who compiled a trigonometric table that
measured the length of chord subtending a various angles in a
circle of a fixed radius r.
7. Hipparchus is considered the greatest astronomical observer,
and by some the greatest astronomer of antiquity. He was the first
Greek to develop quantitative and accurate models for the motion of
the Sun and Moon. With his solar and lunar theories and his
numerical trigonometry, he was probably the first to develop a
reliable method to predict solar eclipses.
8. Key Concepts Trigonometric ratios Trigonometric ratios at
specific angles (0, 30, 45, 60, 90) Trigonometric ratios at
complementary angles Trigonometric Identities Angle of Elevation
Angle of Depression
9. Methodology Previous knowledge testing Demonstration Method
Explanation by giving examples Relating to daily life Concrete to
abstract thinking Simple to complex Learning by doing
10. B A C Sin / Cosec P (pandit) H (har) Cos / Sec B (badri) H
(har) Tan / Cot P (prasad) B (bole) This is pretty easy! BASE (B)
PERPENDICULAR (P)
11. A 0 30 45 6 0 90 Sin A 0 1 Cos A 1 0 Tan A 0 1 Not Defined
Cosec A Not Defined 2 1 Sec A 1 2 Not Defined Cot A Not Defined 1
0
12. Trigonometric Ratio of complementary Angles sin( 90 - ) =
cos cos( 90- ) = sin tan( 90 - ) = cot cot( 90 - ) = tan sec( 90 -
) = cosec cosec( 90 - ) = sec
14. Vocabulary / Terminology Used Right Triangle Base,
perpendicular and hypotenuse Sine ,Cosine, Tangent, Cotangent,
Secant and Cosecant Elevation Depression
15. Life Skills Integrated Identify and problem solving
Attitudes It enhance Scientific Skill which improves critical
thinking.
16. Historically, it was developed for astronomy and geography,
but scientists have been using it for centuries for other purposes,
too. Besides other fields of mathematics, trigonometry is used in
physics, engineering, and chemistry. Within mathematics,
trigonometry is used primarily in calculus (which is perhaps its
greatest application), linear algebra, and statistics. Since these
fields are used throughout the natural and social sciences,
trigonometry is a very useful subject to know.
17. Applications Measuring inaccessible lengths Height of a
building (tree, tower, etc.) Width of a river (canyon, etc.) Angle
of elevation and depression 17
18. 18 Angle of Elevation It is the angle formed by the line of
sight with the horizontal when it is above the horizontal level,
i.e., the case when we raise our head to look at the object. A
HORIZONTAL LEVEL ANGLE OF ELEVATION
19. 19 Angle of Depression It is the angle formed by the line
of sight with the horizontal when it is below the horizontal level,
i.e., the case when we lower our head to look at the object. A
HORIZONTAL LEVEL ANGLE OF DEPRESSION
20. Application: Height To establish the height of a building,
a person walks 120 ft away from the building. At that point an
angle of elevation of 30 is formed when looking at the top of the
building. 20 30 120 ft h = ? H = 69.28 ft
21. Application: Height An observer on top of a hill measures
an angle of depression of 60 when looking at a truck parked in the
valley below. If the truck is 55 ft from the base of the hill, how
high is the hill? 21 60 h = ? 55 ft H = 95.26 ft
22. 22
23. 23 ? 70 ft 30 D = 40.41 ft
24. 24 h = ? HORIZONTAL LEVEL It is an instrument which is used
to measure the height of distant objects using trigonometric
concepts. Here, the height of the tree using T. concepts, h = tan
*(x) x units
25. Triangle Jokes Trigonometry jokes are a sine of the times.
Fake tan: The major threat to trigonometry Q. What does
trigonometry have in common with a beach? A: Tan Gents Trigonometry
for farmers: swine and coswine. When were trigonometry tables used?
B. C., Before Calculators.
26. 26 Trigonometry begins in the right triangle, but it doesnt
have to be restricted to triangles. The trigonometric functions
carry the ideas of triangle trigonometry into a broader world of
real-valued functions and wave forms. Trig functions are the
relationships amongst various sides in right triangles. The
enormous number of applications of trigonometry include astronomy,
geography, optics, electronics, probability theory, statistics,
biology, medical imaging (CAT scans and ultrasound), pharmacy,
seismology, land surveying, architecture. I get it!
27. The Pyramids of Giza Primitive forms of trigonometry were
used in the construction of these wonders of the world.
28. Architecture In architecture, trigonometry plays a massive
role in the compilation of building plans. For example, architects
would have to calculate exact angles of intersection for components
of their structure to ensure stability and safety. Some instances
of trigonometric use in architecture include arches, domes, support
beams, and suspension bridges. Architecture remains one of the most
important sectors of our society as they plan the design of
buildings and ensure that they are able to withstand pressures from
inside.
29. How do I get involved in Architecture? Classes to TAke
Salary and Benefits Physics Geometry Trigonometry Pre-Calculus and
Calculus Engineering 3-D Design Drawing * Art classes will assist
you in being able to conceptualize objects! Most architects start
out with a salary of Rs 371268 + per year , and through experience,
may earn up to Rs 500000 or above Becoming an architect will open
you to many more careers, including interior design and building
design!
30. Jantar Mantar observatory For millenia, trigonometry has
played a major role in calculating distances between stellar
objects and their paths.
31. Astronomy Astronomy has been studied for millennia by
civilizations in all regions of the world. In our modern age, being
able to apply Astronomy helps us to calculate distances between
stars and learn more about the universe. Astronomers use the method
of parallax, or the movement of the star against the background as
we orbit the sun, to discover new information about galaxies.
Menelaus Theorem helps astronomers gather information by providing
a backdrop in spherical triangle calculation.
32. How do I get involved in Astronomy? Classes to take Salary
and Benefits Physics Electronics Advanced Math Geometry Precalculus
and Calculus Astrophysics The median salary for Astronomers is
salary packets ranging from Rs. 8 lacs per annum to around Rs. 10
lacs per annum for those in senior positions. As an aside to being
an astronomer, one can also acquire a teaching position at a
research university!
33. Grand Canyon Skywalk Geologists had to measure the amount
of pressure that surrounding rocks could withstand before
constructing the skywalk.
34. Geology Trigonometry is used in geology to estimate the
true dip of bedding angles. Calculating the true dip allows
geologists to determine the slope stability. Although not often
regarded as an integral profession, geologists contribute to the
safety of many building foundations. Any adverse bedding conditions
can result in slope failure and the entire collapse of a
structure.
35. How do I get involved in Geology? Classes to take Salary
and Benefits Physics Chemistry Pre-calculus and Calculus Geometry
Geochemistry Seismology Median wages for Geologists are around Rs
500000+ a year. However, if involved in oil extraction, earnings
could increase to over Rs 700000+ a year. Geologists can be very
flexible in what they decide to do. There are a multitude of job
options ranging from agriculture to tourism that require the work
of a geologist.
36. Reference offline/online:- NCERT text book of mathematics
www.britanica.com www.mathsfun.com
http://math.lotsoflessons.com
37. Home Assignment 1. Related Exercises from text book and
exemplar book of mathematics. 2. Activity:- to prepare a chart of
T-ratios, T-ratios at specific angles, T-identities. 3. Project:-
make clinometer ( in group)
38. Common Error Committed
39. Common Error Committed
40. Common Error Committed
41. Common Error Committed
42. Common Error Committed
43. Common Error Committed
44. Common Error Committed
45. Common Error Committed
46. Common Error Committed
47. Common Error Committed
48. Common Error Committed
49. Common Error Committed
50. Remedial Plan Make awareness regarding the ratio by giving
examples from daily life. Group leaders will be assigned to make
correction by guiding them. Similar problem assigned to practices
related to each concept will be given.