The value of the polynomial 5x–4x2+3, when x=−1 is A) −6 B) 6 C) 2 D) −2
The answer is A (−6). Given p(x)=5x–4x2+3 ...(i) On putting x=−1 in eq.(i) we get, p(−1)=5(−1)−4(−1)2+3=−5−4+3∴p(−1)=−6
Find the value of the polynomial 5x−4x2+3 at (i) x=0 (ii) x=−1 (iii) x=2
If one zero of the quadratic polynomial kx2+3x+k is 2 then the value of k is
(a) 56 (b) −56 (c) 65 (d) −65