Question

if (x^2+3x+5)(x^2-3x+5)=m^2-n^2 then m=________

Answer 1

(x^2+3x+5)(x^2-3x+5)
=》[(x^2)+(3x+5)][(x^2)-(3x+5)]
using (a+b)(a-b) = (a^2)-(b^2)
=》[(x^2)^2]-(3x+5)^2
on comparing [(x^2)^2]-(3x+5)^2 with m^2-n^2

we get m^2=x^4
•°• m= x^2
;