Current location - Training Enrollment Network - Mathematics courses - 20 17 the national mathematics college entrance examination is entitled as an example. why does the answer end with m > minus one?
20 17 the national mathematics college entrance examination is entitled as an example. why does the answer end with m > minus one?
From the previous derivation, we can know that the discriminant of the root is = 16 (4k 2-m 2+ 1) > 0, and then k=-(m+ 1)/2.
So substitute k, 4k 2-m 2+1> 0.
4ⅹ[-(m+ 1)/2]^2-m^2+ 1>； 0
Simplify to 2m+2 >0 to get m>- 1
So if and only if m> is-1, the discriminant of root -0 is obtained in this way.