Question

what is the trick to find 40-50 square only and this trick gave answer in 3 second​

Answer 1

Use :

( a + b )² for values other that 45 .

Remember that you must remember :

40² = 1600

50² = 2500

45² = 2025

4 × ( 4 + 1 ) = 20

5² = 25

This way 45² can be found .

But there is a technique for others also .

41² = 1681

40² = 1600

41² = 1600 + 1² + 2×40

= 1681

42² = 1764

40² + 2² + 2 × 2 × 40

= 1764

But near 50 s :

48² = 50² + 2² - 2 × 2 × 50

= 2500 + 4 - 200

= 2304

Hope you understand ^^"    

Answer 2

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.Square and Square Root of two digit using formula

.Get Square and Square Root using three digit formula

.Square and Square Root of 100 base method.

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