Question

which of the following should be added to make x^4+64 a perfect square

imagine :a^2 +b^2+2ab
now to the data x^4+64
a^2=(x^2)2
b^2=8^2
2ab=2×8×x^2​

Answer 1

16x2

Step-by-step explanation:

x2 + 64 = (x2)2 + 82 – 2 x (x2) x 8

= (x2 – 8)2

2 x (x2) x 8 must be added

i.e, 16x2 must be added