a4 + 4 এর উৎপাদক কি কি?
A
a2+2a+2 a2-2a+2
B
a2+2a+2a2-2a-2
C
a2-2a+2 a2+2a-2
D
a2-2a-2 a2-2a+2
Correct Answer: a2+2a+2 a2-2a+2
a4 + 4 = (a2)2 + 2.a2.2 + (2)2 - 4a2 = (a2 + 2)2 - (2a)2 = (a2 + 2a + 2)(a2 - 2a + 2)