if x=2 and x=0 are the zeroes of the polynomial f(x)=2x³-5x²+ax+b,find the value of a and b
plz help
Answers
Answered by
6
I hope it will help u☺️☺️☺️☺️
Attachments:
anujtanwar:
thnks
wlcm
wrong
value of a = "2"
u have written a = "-2" , it is wrong
16-20= -4 and if we will move -4 to rhs it will be equal to +4
thanks for the correction
wlcm:-)
Answered by
4
hey mate!
since, x = 2
so, f(x) = 2x³-5x²+ax+b
=> f(2) = 2(2)³-5(2)²+a(2)+b
=> 0 = 16 - 20 + 2a +b
=> 0 = -4 +2a+b
=> 0+4 = 2a+b
=> 4/2 = a+b
=> 2 = a+b ..............(i)
now, when x = 0
=> f(0) = 2(0)³-5(0)²+a(0)+b
=> 0 = 0-0+0a+b
=> 0 = b .......(ii)
so, we subtract equation (i) from equation (ii).
=> a+b-b = 2 - 0
=> a = 2
therefore, a+b = 2
=> b = 2-a
=> b = 2-2
=> b = 0.
hope it was helpful!!✌️✌️
since, x = 2
so, f(x) = 2x³-5x²+ax+b
=> f(2) = 2(2)³-5(2)²+a(2)+b
=> 0 = 16 - 20 + 2a +b
=> 0 = -4 +2a+b
=> 0+4 = 2a+b
=> 4/2 = a+b
=> 2 = a+b ..............(i)
now, when x = 0
=> f(0) = 2(0)³-5(0)²+a(0)+b
=> 0 = 0-0+0a+b
=> 0 = b .......(ii)
so, we subtract equation (i) from equation (ii).
=> a+b-b = 2 - 0
=> a = 2
therefore, a+b = 2
=> b = 2-a
=> b = 2-2
=> b = 0.
hope it was helpful!!✌️✌️
Similar questions