If the polynomial ax3 +bx2 - c is divisible by x2 + bx +c then ab =?
Answers
Answered by
31
Answer:
ab = 1
Step-by-step explanation:
- If f(x) is divisible by g(x), then the “remainder” of a long division would equal zero.
- The remainder after dividing f(x) by g(x) is
- [(ab² – ac + b)x + c(ab – 1)]/(x² + bx + c) For the numerator to equal zero, both terms in parentheses have to be equal to zero
=> ab² – ac + b = 0 and ab – 1 = 0
=> ab = 1…….(i)
=> or a=1/b
=> ab² – ac + b = 0
=> ac = ab² + b
=> ab = 1………..(from (i))
=> ac = b + b = 2b
=> c=2b/a
=> c = 2b/(1/b) substituting value of a
=> or C = 2b²
Answered by
5
Hey Buddy
Here's The Answer
--------------------------------------------------
Let
f(x) = ax³ + bx² - c
g(x) = x² + bx + c
Given f(x) is divisible by g(x), which means remained is 0
So,
=> ( ax³ + bx² - c )/( x² + bx + c ) = 0
By the attachment we got the result
=> ( ab² - ac + b )x + ( ab - 1 ) = 0
==> We get two equations
==> x( ab² - ac + b) = 0
=> ab² - ac + b = 0____( 1 )
==> c( ab - 1 = 0 )
=> ab - 1 = 0_______( 2 )
Now from ( 2 )
=> ab = 1 ✓
Hope It Helps
:)
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