9th Standard Syllabus & Materials
9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -கற்கண்டு (இலக்கணம்) - தொடர் இலக்கணம், ஆகுபெயர் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -விரிவானம் (துணைப்பாடம்) - தாய்மைக்கு வறட்சி இல்லை! Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -கவிதை பேழை (செய்யுள்) - மார்கழி பெருவிழா Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உயிருக்கு வேர்-இலக்கணம் - பகுபத உறுப்பிலக்கணம் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil அமுதென்று பேர் - இலக்கணம்-எழுத்து -அளபெடை Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil அமுதென்று பேர்-துணைப்பாடம் - ஆறாம்திணை Important Questions And Answers Study Material - QB365 Set A

Published on: 21/01/2020
Download Tamil Nadu 9th Standard Maths question papers, model tests, one-mark questions, important questions, and public exam papers in PDF format. Free study materials and answer keys for TN State Board students.
Questions + Answers key
Take MCQ Maths Test1.
Find the volume of cube whose side is 10 cm.
2.
Find the value of cos19059'
3.
Find the six trigonometric ratios of the angle \(\theta\) using the given diagram.

4.
A researcher studying the behaviour of mice has recorded the time (in seconds) taken by each mouse to locate its food by considering 13 different mice as 31, 33, 63, 33, 28, 29, 33, 27, 27, 34, 35, 28, 32.Find the median time that mice spent in searching its food.
5.
Using algebraic identity, find the coefficients of x2, x and constant term without actual expansion.
(i) (x + 5)(x + 6)(x + 7)
(ii) (2x + 3)(2x − 5)(2x - 6)
6.
(i) Add 3\(\sqrt{7}\) and 5\(\sqrt{7}\) . Check whether the sum is rational or irrational.
(ii) Subtract 4\(\sqrt{5}\) from 7\(\sqrt{5}\) . Is the answer rational or irrational?
7.
Rationalise the denominator and simplify \(\frac { 5\sqrt { 3 } +\sqrt { 2 } }{ \sqrt { 3 } +\sqrt { 2 } } \)
8.
In a residential area with 600 families \(\frac{3}{5}\) owned scooter, \(\frac{1}{3}\) owned car, \(\frac{1}{4}\) owned bicycle, 120 families owned scooter and car, 86 owned car and bicylce while 90 families owned scooter and bicylce. If \(\frac{1}{15}\) of families owned all the three types of vehicles, then find
(i) the number of families owned atleast two types of vehicle.
(ii) the number of families owned no vehicle.
9.
Verify \(A-(B\cap C)=(A-B)\cup (A-C)\)using Venn diagrams.
10.
The area of a rectangle is x4 + 9x2 + 20 sq. units and its length is x2 + 4 units. Find its breadth in term of x.
11.
ABCD is a parallelogram and AP and CQ are perpendic from vertex A and C on diagonal BD. Show that
(i) ΔAPB ≅ ΔCQD
(ii) AP = CQ

12.
In a class there are 40 students. 26 have opted for Mathematics and 24 have opted for Science. How many student have opted for Mathematics and Science.
13.
Insert the appropriate symbol ∈ (belongs to) or ∉ (does not belong to) in the blanks.
14.
What is the remainder when x2018 + 2018 is divided by x–1
15.
Express the following decimal expression into rational numbers -\(21.21\overline {37}\)
16.
What must be subtracted from 2x4+4x2-3x+7 to get 3x3-x2+2x+1?
17.
Find the degree of the following polynomials \(2\sqrt { 5 } { p }^{ 4 }-\frac { { 8p }^{ 3 } }{ \sqrt { 3 } } +\frac { { 2p }^{ 2 } }{ 7 } \)
18.
Show that the following points A(3, 1), B(6,4) and C(8, 6) lies on a straight line.
19.
Let m || n and l is a transversal Such that ∠1 : ∠2 = 11 : 7. Determine all the eight angles.

1.
Given that side (a) = 10 cm
volume of the cube = a3
= 10 × 10 × 10
= 1000 cm3
2.
| 0' | 6' | 12' | 18' | 24' | 30' | 36' | 42' | 48' | 54' | Mean Difference | |||||
| 0.00 | 0.10 | 0.20 | 0.30 | 0.40 | 0.50 | 0.60 | 0.70 | 0.80 | 0.90 | 1 | 2 | 3 | 4 | 5 | |
| 190 | 0.9403 | 5 | |||||||||||||
write 19059' = 19054' + 5'
From the table we have, cos19054' = 0.9403
3.
By Pythagoras theorem,
\(AB=\sqrt { { BC }^{ 2 }{ AC }^{ 2 } } \)
= \(\sqrt { { \left( 25 \right) }^{ 2 }-{ 7 }^{ 2 } } \)
= \(\sqrt { 625-49 } =\sqrt { 576 } \) = 24
The six trignometric ratios are
\(sin\theta =\frac { opposite\ side }{ hypotenuse } =\frac { 7 }{ 25 } \)
\(tan\theta =\frac { oppositeside }{ adjacent\ side } =\frac { 7 }{ 24 } \)
\(sec\theta =\frac { hypotenuse }{ adjacent\ side } =\frac { 25 }{ 24 } \)
\(cos\theta =\frac { adjacentside }{ hypotenuse } =\frac { 24 }{ 25 } \)
\(cosec\theta =\frac { hypotenuse }{ oppositeside } =\frac { 25 }{ 7 } \)
\(cot \theta\ \frac { adjacentside }{ oppositeside } =\frac { 24 }{ 7 } \)

4.
31, 33, 63, 33, 28, 29, 33, 27, 27, 34, 35, 28, 32
Writing in ascending order we get
27, 27, 28, 28, 29, 31, 32, 33, 33, 33, 34, 35, 36
Number of values = 13 which is an odd number
\(\therefore\) Median =\(\left( \cfrac{13+1}{2} \right) \) Value
= \(\left(\cfrac{14}{2}\right)^{th}\) Value = 7th value
= 32
5.
(i) (x + 5)(x + 6)(x + 7)
Co-efficient of x2 = a + b + c = 5 + 6 + 7 = 18
Co-efficient of x2= ab + bc + ca = (5\(\times\)6)+(6\(\times\)7)+(7\(\times\)5)
= 30 + 42 + 35 = 107
Constant term = abc = 5\(\times\)6\(\times\)7
Co-efficient of constant term = 210
(ii) (2x + 3)(2x - 5)(2x - 6)
ஃ Co-efficient of x2= 4(a+b+c) = 4(3+(-5)+(-6))
= 4\(\times\)(-8) = -32
Co-efficient of x = 2(ab+bc+ca)
= 2[3x(-5)+(-5)(-6)+(-6)(3)]
= 2[-15+30-18] = 2x(-3) = -6
Constant term = abc = 3x(-5)x(-6) = 90
6.
(i) 3\(\sqrt{7}\) + 5\(\sqrt{7}\) = (3 + 5)\(\sqrt{7}\) = 8\(\sqrt{7}\). The answer is irrational.
(ii) 7\(\sqrt{5}\) - 4\(\sqrt{5}\) = (7 - 4)\(\sqrt{5}\) = 3\(\sqrt{5}\). The answer is irrational.
7.
\(\frac { 5\sqrt { 3 } +\sqrt { 2 } }{ \sqrt { 3 } +\sqrt { 2 } } =\frac{(5\sqrt{3}+\sqrt{2})\times(\sqrt{3}-\sqrt{2})}{(\sqrt{3}+\sqrt{2})\times(\sqrt{3}-\sqrt{2})}\)
=\(\frac{5\sqrt{3}\times\sqrt{3}+\sqrt{2}\times\sqrt{3}-5\sqrt{3}\times\sqrt{2}-\sqrt{2}^2}{\sqrt{3}^2-\sqrt{2}^2}\)
=\(\frac{5\times3+\sqrt{6}-5\sqrt{6}-2}{3-2}=\frac{13-4\sqrt{6}}{1}=13-4\sqrt{6}\)
8.
Let S, C and B represent sets of families who owned Scooter, Car and Bicycle respectively.
Given, n(U)=600 n(S) =\(\frac{3}{5}\) \(\times\) 600 = 360
n(C) = \(\frac{1}{3}\) \(\times\) 600 = 200 n(B)=\(\frac{1}{4}\) \(\times\) 600 = 150
n(S⋂C⋂B)=\(\frac{2}{15}\) \(\times\) 600 = 80
From Venn diagram,
(i) The number of families owned atleast two types of vehicles = 40 + 6 + 10 + 80 = 136
(ii) The number of families owned no vehicle
= 600 – (owned atleast one vehicle)
= 600- (230 + 40 + 74 + 6 + 54 + 10 + 80)
= 600 - 494 = 106

9.

ஃ A-(B∩C)=(A-B)U(A-C)
Hence it is proved.
10.
Let the breadth of the rectangle be "b"
Length of the rectangle = x2 + 4
Area of the rectangle = x4 + 9x2 + 20

Length x Breadth = x4 + 9x2 + 20
(x4 + 4)x b = x4 + 9x2 + 20
b = \(\frac{x^4+9x^2+20}{x^2+4}\)
= x2+ 5
Breadth of the rectangle = x2+ 5
11.
(i) In ΔAPB and ΔCQD we have
ㄥAPB = ㄥCQD (90o each)
AB = CD (opposite sides of parallelogram ABCD)
ㄥABP = ㄥCDQ (AB II CD and AD is a transversal)
Using ASA congruency we have,
ㄥAPB ≅ ㄥCQD
(ii) Since ΔAPB ≅ ㄥCQD
∴ Their corresponding parts are equal.
∴ AP = CQ.
12.
Let M be the set of students opting for Mathematics.
Let S be the set of students opting for Science.
n (M U S) = 40, n (M) = 26, n (S) = 24
n (M U S) = n (M) + n (S) - n (M n S)
40 = 26 + 24 - n (M n S)
n (M n S) = 26 + 24 - 40
= 50 - 40 = 10
∴ Number of students opted for Mathematics and Science = 10
13.

14.
p(x) = x2018 + 2018
When it is divided by x - 1,
p( 1) = 12018+ 2018
= 1 + 2018
= 2019
The Remainder : 2019
15.
Let x = -21.213777 ...... \(\rightarrow\) (1)
Here period of decimal is 4,multiply equation (1) by 10000
10000 x = -21213, 7.777 .............. (2)
(2) - (1)
9999 x = 212116.5640
\( x =\frac{-212116.5640}{9999} \)
\( x =\frac{-2121165640}{99990000} \)
\( =\frac{-190924}{9000}=\frac{-47731}{2250} \)
16.
2x4 + 4x2 - 3x + 7 - (3x3 - x2 + 2x + 1)
= 2x4 + 4x2 - 3x + 7 - 3x3 + x2 - 2x - 1
= 2x4 - 3x3 + 4x2 + x2 - 3x - 2x + 7 - 1
= 2x4 - 3x3 + 5x2 - 5x + 6
2x4 - 3x3 + 5x2 - 5x + 6 must be subtracted to get 3x3 - x2 + 2x + 1.
17.
The degree of the polynomial is 4
18.
Using the distance formula, we have
\(AB=\sqrt { \left( 6-3 \right) ^{ 2 }+\left( 4-1 \right) ^{ 2 } } =\sqrt { 9+9 } =\sqrt { 18 } =3\sqrt { 2 } \)
\(BC=\sqrt { \left( 8-6 \right) ^{ 2 }+\left( 6-4 \right) ^{ 2 } } =\sqrt { 4+4 } =\sqrt { 8 } =2\sqrt { 2 } \)
\(AC=\sqrt { \left( 8-3 \right) ^{ 2 }+\left( 6-1 \right) ^{ 2 } } =\sqrt { 25+25 } =\sqrt { 50 } =5\sqrt { 2 } \)
\(AB+BC=3\sqrt { 2 } +3\sqrt { 2 } =5\sqrt { 2 } =AC\)
Therefore the points lie on a straight line.
19.
\(\angle 1:\angle 2=11:7\)
\(\angle 1+\angle 2=180^0\) (Angle of a straight line)
Divide 180° in the ratio 11 : 7
Total ratio 11 + 7 = 18
\(\angle 1=\frac{11}{18}\times180^0=110^0\)
\(\angle 2=\frac{7}{18}\times180^0=70^0\)
\(\angle 3=\angle 1=110^0\)(Vertically opposite angles)
\(\angle 4=\angle 2=70^0\)(Vertically opposite angles)
\(\angle 5=\angle 1=110^0\)(Corresponding angles)
\(\angle 6=\angle 2=70^0\)(Corresponding angles)
\(\angle 7=\angle 5=110^0\)(Vertically opposite angles)
\(\angle 8=\angle 6=70^0\)(Vertically opposite angles )
\(\therefore\) ∠1 = 110°, ∠2 = 70°, ∠3 = 110°, ∠4 = 70°, ∠5 = 110°, ∠6 = 70°, ∠ 7 = 110° ∠8 = 70°.
9th Standard Syllabus & Materials
9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - திருக்குறள் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - மணிமேகலை Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - ஏறு தழுவுதல் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உயிருக்கு வேர் - தண்ணீர் Important Questions And Answers Study Material - QB365 Set A
Tamilnadu Stateboard 9th Standard Subjects
Tamilnadu Stateboard Standards