Academy imparting Knowledge, Attitude, Skills and Habits (AKASH) : January 2020

Saturday 25 January 2020

COMMERCIAL MATHEMATICS - PART - 04

CALCULATION OF COMPOUND INTEREST WITH DIFFERENT INTEREST VALUES

COMMERCIAL MATHEMATICS - PART - 03

COMMERCIAL MATHEMATICS - PART - 03 CALCULATION OF COMPOUND WITH DIFFERENT INTEREST CALCULATIONS

COMMERCIAL MATHEMATICS - PART - 02

COMPARISON OF SIMPLE AND COMPOUND INTEREST

COMMERCIAL MATHEMATICS - PART - 01

CALCULATION OF SIMPLE AND COMPOUND INTEREST.

TRIGONOMETRY - PART - 50 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS.

From the adjoining fig. find the value of sin x and cos y.

TRIGONOMETRY - PART - 49 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS.

In the adjoining fig. AM is perpendicular to BC. If tan B = 3/4 and tan C = 5/12 and BC = 56 cm. Calculate the length of AM.

TRIGONOMETRY - PART - 48 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS.

Triangle ABC is right-angled at B, D is the mid-point of BC, AC = 5 units, BC = 4 units and triangle BAD is Ꝋ . Find the value of (i) tan Ꝋ (ii) sin Ꝋ and (iii) sin^2 Ꝋ + cos^2 Ꝋ.

TRIGONOMETRY - PART - 47 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS.

In the adjoining fig., triangle ABC is right-angled at B and tan A = 4 / 3. If AC is 15 cm, find the lengths of AB and BC.

TRIGONOMETRY - PART - 46 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS.

If 3 cos A = 4 sin A; find the value of:

4 cos^2 A – 3 sin ^2 A + 2.

TRIGONOMETRY - PART - 45 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS.

If cos A = 9/41; find the value of:

1 / sin^2 A – cot ^2 A.

TRIGONOMETRY - PART - 44 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS.

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 35

In triangle ABC, angle B = 90 degrees, AB = 40, AC + BC = 80. Find (i) sin A (ii) cos A (iii) tan C.

TRIGONOMETRY - PART - 43 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS.

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 34

If cos A = 2 (m n)^1/2 / m + n, find the value of sin A (given m>n).

TRIGONOMETRY - PART - 42 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 33

In triangle ABC angle C = 90 degrees, AB = 20 and BC = 12, D is a point in side AC such that CD = 9. Taking angle BDC = x find

(i) sin angle ABC and (ii) tan x – cos x + 3 sin x.

Wednesday 15 January 2020

DAILY TEN WORDS - HIGH-FREQUENCY WORDS IN ENGLISH - Z - LIST - COMPILED BY - ZENMURALI

31. zonk (v) fall asleep fast, as when one is extremely tired [adj – zonked]

# ஜோங் (வி.சொல்) வேலை முடிந்தவுடன் விரைவில் அயர்ந்து தூங்குதல்

# Hard labourers zonk after completion of their work.

32. zoom (v) change the view of an image so as to magnify or shrink it, e.g. when showing a picture on a computer or changing the focal length of a camera lens [n – zoom, adj - zoomable]

# ஜூம் (வி.சொல்) உருவகத்தை பெரிதாக காட்டு

# The police zoomed on the CCTV footage to investigate more on the theft.

33. zoomorphism (n) the representation of animal forms in decorative art or symbolism [adj – zoomorphic]

தெய்வத்தை விலங்குருவத்தில் காட்டுதல்

# Zoomorphism was practiced by the Indians in olden times.

34. zoophagous (adj) (of animals) carnivorous

மாமிச பட்சினிகள்

# Lions and Tigers are zoophagous animals.

35. zoophobia (n) fear or dread of animals

விலங்குகள் கண்டு இயற்கை மீறிய பேரச்சம்

# Children generally have zoophobia, but eventually take them as pet animals.

36. zoophyte (n) any of various invertebrate animals resembling a plant such as a sea anemone, coral or sponge

செடி வடிவமுடைய விலங்கு வகை
# Worms are examples of a zoophyte.

37. zygote (n) the cell produced by the union of two gametes [adj – zygotic, adv – zygotically]

இரு பாலணு இணைவுப் பொருள்

# The zygote is the first stage in the development of the fetus.

38. zymology (n) the science dealing with fermentation [adj – zymologic]

புளித்தெழும்புதல், நொதித்தல்

# Zymology contributes a lot to the brewing of liquor.

39. zymotic (adj) of or relating to or causing fermentation; relating to or caused by

infection [n – zymosis, adv - zymotically]

நொதித்தல் மற்றும் தொற்று நோய் தொடர்பான

# Diphtheria is not a zymotic disease.

40. zymurgy (n) the branch of chemistry concerned with fermentation (as in making wine or brewing or distilling); the practice of fermentation

வேதியலின் ஒரு பகுதி நொதித்தலாகும், புளித்தெழும்பும் நிகழ்வாகும்

# Women prepare curd but do not know that it is due to zymurgy.

DAILY TEN WORDS - HIGH-FREQUENCY WORDS IN ENGLISH - Z - LIST - COMPILED BY - ZENMURALI

21. zing (n) a brief high-pitched buzzing or humming sound, a quality that makes something interesting or exciting; enthusiasm or energy [adj – zingy, v - zing]

ஊக்கம், ஆர்வம், சக்தி

# Boxing requires both zing and physical strength.

22. zinger (n) a striking, amusing or caustic remark

ஒரு உறைக்கத்தக்க, வேடிக்கையாக அல்லது கேலியான கருத்து

# Zinger political debates are common in all TV channel.

Ant. compliment, flattery, praise

23. zion (n) an imaginary place considered to be perfect or ideal, the hill of Jerusalem on which the city of David was built, nonconformist chapel [n – zionist]

பண்டைய ஜெருசேலம் நகரம், வானுலகு

# The Jewish people believe Zion is their holiest place.

24. zip (v) (computing) compress a file or batch of files into on compressed package [n – zip]

கோப்புகளை சுருக்கு

# The guide advised the research scholar to zip the thesis and mail to him.

25. zip code (n) in the US, a series of numbers that forms part of an address, and which is used to help organize post so that it can be delivered more quickly

அஞ்சல் குறியீடு

# It is always good to send letters with proper zip code.

26. zippy (adj) quick and energetic, marked by lively action [n – zippiness]

வேகத்துடனும் சத்தியுடனும் செயல்படுதல், உயிரோடத்துடன் செயல்படுவதை குறித்தல்

# Tennis and basketball are zippy games.

Ant. inactive, slow, unenergetic

27. zodiacal (adj) relating to an area of the sky through which the sun, moon, and most of the planets appear to move, divided into twelve equal parts, each with a name and symbol, and each connected with an exact time of year [n – zodiac]

ஜோதிடவியலில் பன்னிரண்டு இராசிகளைக் குறிக்கும் சொல்

# People now look into their zodiac sign message before the start of each day.

28. zoilean (adj) hypocritical [n – zoiliest]

பாசாங்குத்தனத்துடன், உள்ளொன்று வைத்து புறம் ஒன்று பேசுவது

# Hitler was famous for his zoilean speech and manners.

Ant. honesty, forthright

29. zombie (n) someone who acts or responds in a mechanical or apathetic way; a dead body that has been brought back to life by a supernatural force [adj – zombielike, adv – zombify]

ஆர்வமில்லாமல் இந்திரத்தனமாக செய்யும் நபர் (சோம்பேறி), அதீத சக்தியால் மரித்த உடலை மீண்டும் உயிர்ப்பிக்கவைப்பது

# A zombie person is a curse to the society besides curse to himself.

30. zone (n) area, section, region [adj – zonal]

பிரேதேசம், மண்டலம்

# Danger zone boards in the sea shore are to alert the tourists.

Tuesday 14 January 2020

TRIGONOMETRY - PART - 41 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 32

If 2 cot A = 3, find the value of:

5 sin A – 2 cos A / 6 cos A + sin A

TRIGONOMETRY - PART - 40 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 31

If 6 tan A – 5 = 0, find the value of:

5 sin A – cos A / 5 cos A + 9 sin A

TRIGONOMETRY - PART - 39 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 30

If 5 cos A = 6 sin A, evaluate:

(i) tan A

(ii) 12 sin A – 3 cos A / 12 sin A + 3 cos A

TRIGONOMETRY - PART - 38 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 29

If cosec A + sin A = 26 /5, find the value of

cosec^2 + sin^2 A

TRIGONOMETRY - PART - 37 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 28

If 5 cos A = 3, evaluate

cosec A – cot A / cosec A + cot A

TRIGONOMETRY - PART - 36 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 27

If sec A = 1.414 find:

3 cot^2 A + 2 sin^2 A / tan^2 A – cos^2 A

TRIGONOMETRY - PART - 35 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 26

From the given fig. below evaluate:

10 / sin x + 6 /sin y – 6 cot y

TRIGONOMETRY - PART - 34 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 25

If sin A = 1.732 /2 and cos B = 1.732 /2, find the value of: tan A – tan B / 1 + tan A tan B

TRIGONOMETRY - PART - 33 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 24

If 2 sin x = 1.732, evaluate

(i) sin^3 x – 3 sin x

(ii) 3 cos x – 4 cos^3 x

TRIGONOMETRY - PART - 32 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 23

In rectangle ABCD, diagonal BD = 26 cm and cotangent of angle ABD = 1.5. Find the area and perimeter of the rectangle ABCD.

TRIGONOMETRY - PART - 31 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 22

If sin A = cos , find the value of

2 tan^2 A – 2 sec^2 A + 5

TRIGONOMETRY - PART - 30 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 21

Given : q tan A = p, find the value of:

p sin A – q cos A /p sin A + q cos A

TRIGONOMETRY - PART - 29 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 20

In a triangle ABC, AD is perpendicular to BC, sin B = 0.8, BD = 9 cm and tan C = 1. Find the length of AB, AD, AC and DC.

TRIGONOMETRY - PART - 28 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 19

In triangle ABC, AB = AC = 15 cm and BC = 18 cm.

Find: (i) cos B (ii) sin C (iii) tan^2 B – sec^2 B + 2

TRIGONOMETRY - PART - 27 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 18

In rhombus ABCD, diagonals AC and BD intersect each other at point 0.

If cosine of angle CAB is 0.6 and OB = 8 cm, find the lengths of the side and diagonals of the rhombus.

TRIGONOMETRY - PART - 26 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 17

In triangle ABC, Angle B = 90 degrees and

tan A = 0.75.

If AC = 30 cm, find the lengths of AB and BC.

TRIGONOMETRY - PART - 25 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 16

If 3 cos A = 4 sin A, find the value of:

(i) cos A (ii) 3 – cot ^2 A + cosec ^2 A.

TRIGONOMETRY - PART - 24 - TRIGONOMETRICAL RATIOS - 100 PROBLEMS

ICSE MATHS CLASS 9 – PAGE -294

EXERCISE – 22(B) – PROBLEM – 15

In the given fig. angle C is 90 degrees and D is the mid-point of AC Find (i) tan angle CAB / tan angle CDB and (ii) (i) tan angle ABC / tan angle DBC