If x2 + 2x-3 is factor of x4+6x3+2ax2+bx-3a find the value of a nd b
Answers
Answer:
a=5
b=-2
Step-by-step explanation:
now first we find the value of x
x2+2x−3
x2+3x−x−3
x(x+3)−1(x+3)
(x−1)(x+3)
x=1
x=−3
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now put the value of x in f(x)
f (x) = x 4 + 6 x 3 + 2 a x 2 + b x - 3 a
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when x = 1 then
f(×)=1+6+2a+b-3a
f(×)=7-a+b.......eqn1
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when x = -3
f(×)=(-3)^4+6(-3)^3+2a(-3)^2+b(-3)-3a
f(×)=81-162+18a-3b-3a
f (×) = 15a - 3b - 81....eqn2
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from eqn1 and eqn2
multiply eqn 1 with 3..we have
3b-3a+21
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add this eqn in eqn2
12a-60=0
12a=60
a = 5
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put value of a in eqn1...we have
7-5+b=0
b = -2
======================================
THANK UH
HOPE THIS WILL HELP UH
Answer:
A = 5
B = -2
Step-by-step explanation:
>>>x2+2x−3
>>>x2+3x−x−3
>>>x(x+3)−1(x+3)
>>>(x−1)(x+3)
>>>>>x=1
>>>>x=−3
Put value of x in f(x)
f(x)=x4+6x3+2ax2+bx-3a
=====================
When x=1 then:
f(×)=1+6+2a+b-3a
f(×)=7-a+b.......eqn1
when x = -3
f(×)=(-3)^4+6(-3)^3+2a(-3)^2+b(-3)-3a
f(×)=81-162+18a-3b-3a
f(×)=15a-3b-81....eqn2
From, eqn1 and eqn2
Multiply, eqn 1 with 3..we have
3b-3a+21
Add this eqn in eqn2
12a-60=0
12a=60
a=5
put value of a in eqn1...we have
7-5+b=0
b= -2
Verify answer by putting value of a and b in f(×)
Hope My answer Helpz You!!