Question

25. Evaluate 42 x 42 by using Identity​

Answer 1

Answer:

42x42

1764.............................

Answer 2

Answer:

(40+2) (40+2)

(40+2)^2

using identity( a+ b) ^2 = a^2+b^2+ab

so,

a=40 , b= 2

then,

(40) ^2 + (2) ^2 + (40) (2)

1600+4+80

1600+84

1,684

this is your correct answer