(–1) = 1. Is –1, a square root of 1?
(–2)2 = 4. Is –2, a square root of 4?
(–9)2 = 81. Is –9, a square root of 81?
By repeated subtraction of odd numbers starting from 1, find whether the following numbers are perfect squares or not? If the number is a perfect square, then find its square root.
(i) 121 (ii) 55 (iii) 36
(iv) 49 (v) 90
What could be the possible ‘one’s’ digits of the square root of each of the following numbers?
(i) 9801 (ii) 99856 (iii) 998001 (iv) 657666025
Without doing any calculation, find the numbers which are surely not perfect squares.
(i) 152 (ii) 257 (iii) 408 (iv) 441
Can we say that if a perfect square is of n-digits, then its square root will have digits if n is even of if n is odd?
Without calculating square roots, find the number of digits in the square root of the following numbers.
(i) 25600 (ii) 100000000 (iii) 36864
Estimate the value of the following to the nearest whole number.
(i) (ii) (iii) (iv)
(i)
∵ 102 = 100, 92 = 81, 82 = 64
and 80 is between 64 and 81.
i.e. 64 < 80 < 81
or 82 < 80 < 92
or
Thus, lies between 8 and 9.
We know that 302 = 900, 312 = 961, 322 = 1024
∴ 1000 lies between 961 and 1024.
i.e. 916 < 1000 < 1024
or 312 < 1000 < 322
or
Thus, lies between 31 and 32.
(iii)
We have 182 = 324, 192 = 361
Since, 350 lies between 324 and 316.
i.e. 324 < 350 < 361
or 182 < 350 < 192
or
Thus, lies between 18 and 19.
(iv)
∵ 222 = 484 and 232 = 529
Since. 500 lies between 484 and 529
i.e. 484 < 500 < 529
or 222 < 500 < 232
or
Thus, lies between 22 and 23.
Find the number of digits in the square root of each of the following numbers (without any calculation).
(i) 64 (ii) 144 (iii) 4489
(iv) 27225 (v) 390625