Question

Pls solve these 2 problems correctly....

Answer 1

1)Since the product of zeros =c/a,
c=-6 , a=a and product of zeros is given i.e, 4
=>c/a=4
=>-6/a=4
=>-6=4a
=>-6/4=a
=>a=-3/2.
2)X+1 is a factor of 2x³+ax²+2bx+1

x+1 = 0

x = -1
2(-1)³+a(-1)²+2b(-1)+1 = 0
2(-1) + a(1) - 2b + 1 = 0
-2+a-2b+1 = 0
a-2b-1 = 0
a-2b = 1

Multiply it by 2,

2(a-2b) = 2(1)

2a-4b = 2 -----(1)

Given,

2a-3b = 0 ------(2)

(1) - (2)

2a-4b = 2
-{2a-3b = 0}
––––––––
-b = 2

b = -2
2a - 3(-2) = 0
2a+6 = 0
2a = -6
a = -6/2
a = -3 therefore, a = -3 and b = -2