Important Questions for Class 8 Maths Chapter 5: The important questions for Class 8 Maths Chapter 5 Squares and Square Roots are helpful for Class 8 students. This chapter covers essential topics like finding the square of a number, calculating square roots, and understanding perfect squares.
By solving these questions students can strengthen their understanding of the relationships between numbers and their squares and square roots. These questions also help improve their problem-solving skills, which are crucial for their exams. Practicing these questions makes learning more engaging and effective for students.Important Questions for Class 8 Maths Chapter 5 PDF
Here are some important questions from Class 8 Maths 5 Squares and Square Roots along with their solutions:Q1. Determine whether squares of the 21 is even or odd
Ans. Odd Number (Square of any odd number is odd number)Q2. Determine whether squares of the 38 is even or odd
Ans. Even Number (Square of any even number is even number)Q3. A square Number is of 4 digit then the number of digit in its square root will be odd True/False
Ans. False (Number of digit = 4/2 = 2)Q4. The square of a prime number is prime. True/False
Ans. False (Square of any number is divisible by that number)Q5. The sum of two square numbers is a square number. True/False
Ans. False (Not always)Q6. The difference of two square numbers is a square number.
Ans: False (Not Always)Q7. The product of two square numbers is a square number.
Ans. TrueQ8. Write a Pythagorean triplet whose one member is:
(i) 6
(ii) 14
(iii) 16
(iv) 18
Solution: We know, for any natural number m, 2m, m 2 –1, m 2 +1 is a Pythagorean triplet. (i) 2m = 6 ⇒ m = 6/2 = 3 m 2 –1= 3 2 – 1 = 9–1 = 8 m 2 +1= 3 2 +1 = 9+1 = 10 Therefore, (6, 8, 10) is a Pythagorean triplet. (ii) 2m = 14 ⇒ m = 14/2 = 7 m 2 –1= 7 2 –1 = 49–1 = 48 m 2 +1 = 7 2 +1 = 49+1 = 50 Therefore, (14, 48, 50) is not a Pythagorean triplet. (iii) 2m = 16 ⇒ m = 16/2 = 8 m 2 –1 = 8 2 –1 = 64–1 = 63 m 2 + 1 = 8 2 +1 = 64+1 = 65 Therefore, (16, 63, 65) is a Pythagorean triplet. (iv) 2m = 18 ⇒ m = 18/2 = 9 m 2 –1 = 9 2 –1 = 81–1 = 80 m 2 +1 = 9 2 +1 = 81+1 = 82 Therefore, (18, 80, 82) is a Pythagorean triplet.Q9. (n+1) 2 -n 2 = ?
Solution: (n+1) 2 -n 2 = (n 2 + 2n + 1) – n 2 = 2n + 1Q10. Show that 121 is the sum of 11 odd natural numbers.
Solution: As 121 = 11 2 We know that the sum of first n odd natural numbers is n 2 . Therefore, 121 = sum of first 11 odd natural numbers = 1 + 3 + 5+ 7 + 9 + 11 +13 + 15 + 17 + 19 + 21Q.11. Find the smallest number by which 1100 must be multiplied so that the product becomes a perfect square. Also, find the square root of the perfect square.
Solution: 1100=5*5*2*2*11 Since, 11 does not forms a pair therefore 11 should be multiplied to 1100 to make it a perfect square. 1100*11=12100 Now, 12100=5*5*2*2*11*11 √12100=5*2*11 √ 12100=110Q.12. Find the smallest number by which 9408 must be divided so that in becomes a perfect square. Also, find the square root of the perfect square so obtained.
Solution: To find the smallest number by which 9408 must be divided so that the quotient is a perfect square, we have to find the prime factors of 9408. 9408 = 2*2*2*2*2*2*3*7*7 Prime factors of 9408 are 2, 2, 2, 2, 2, 2. 3, 7, 7 Out of the prime factors of 9408, only 3 is without pair. So, 3 is the number by which 9408 must be divided to make the quotient a perfect square. 9408/3 = 3136 Square root of 3136 56 _____________ 5 | 3136 5 | 25 ___ |______ 106 | 636 6 | 636 |_______ | 000 So, √3136 = 56Q.13. Find the greatest number of seven digits which is a perfect square. What is the square root of this number?
Solution: The greatest seven digit no. is 9999999 < 1,00,00,000 and if we take smallest 8 digit no. it is 1,00,00,000 we take the square root of = 3162.28 which is not a whole number and (3162 )² < (3162.28)² so 9998244 < (3162.28)² so, 9998244 is the greatest 7 digit perfect square