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Mathematics: Post your doubts here!

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when a polynomial f(x) is divided by x - 3,the remainder is -9 and when divided by 2x-1,the remainder is -6.find the remainder when the f(x) is divided by (x-3)(2x-1)(4).

Anum96
Plz help
 
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EEEts a tricky qs. But it has a way.
use the equation; f(x)=p(x)q(x) + r(x)
Where p(x) are the divisors ; q(x) is the quotient and r(x) is the remainder.
Plug in.
f(x) = (x-3)q(x) - 9
f(x) = (2x-1)q(x) - 6

Take any value of x to make the first terms equal to 0
f(3) = (3-3)q(x) - 9
f(1/2) = (2(1/2) - 1) -6

f(3) = -9
f(1/2) = -6

r(x) = ax + b
f(x) = 4(x-3)(2x-1)q(x) + Ax + B.
You have two values. Plug them in
f(3) = A(3) + B
f(1/2) = A(1/2) + B

Now you have the values of f(3) and f(1/2)
-9 = 3A+ B
-6 = 1/2 A + B

Solve them simultaneously;
A = -6/5
B = -27/5
r(x) = -6/5x - 27/5 Answer. :)
 
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EEEts a tricky qs. But it has a way.
use the equation; f(x)=p(x)q(x) + r(x)
Where p(x) are the divisors ; q(x) is the quotient and r(x) is the remainder.
Plug in.
f(x) = (x-3)q(x) - 9
f(x) = (2x-1)q(x) - 6

Take any value of x to make the first terms equal to 0
f(3) = (3-3)q(x) - 9
f(1/2) = (2(1/2) - 1) -6

f(3) = -9
f(1/2) = -6

r(x) = ax + b
f(x) = 4(x-3)(2x-1)q(x) + Ax + B.
You have two values. Plug them in
f(3) = A(3) + B
f(1/2) = A(1/2) + B

Now you have the values of f(3) and f(1/2)
-9 = 3A+ B
-6 = 1/2 A + B

Solve them simultaneously;
A = -6/5
B = -27/5
r(x) = -6/5x - 27/5 Answer. :)
Thank u so much
 
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AOA everyone,
Actually I'm in a really confused state, my problem is related to M1 mechanics and physics....Alright, so we all know that when a simple object like a block of wood moves in a forward direction there is kinetic friction between the block and the floor in the opposite direction.... But things get tricky when it comes to an individual wheel, my mind is actually boggled about *HOW A WHEEL MOVES FORWARD?*. Several pages on Google state that the axle produces two tangential forces on the top and bottom of the wheel and this produces a torque about the axle. Then they state that the friction is opposite to the rotation of the wheel and so it acts in the forward direction causing the wheel to roll forward. But how can friction (forward) ever be greater than the backward force on the wheel produced by the axle. Some articles even mention static friction and rolling friction acting opposite to the direction of motion and all these contradicting statements on the web are confusing me further. Please help me with my query with a detailed and sensible explanation in terms of whatever I stated above. It would be really benign of you. Thanks in advance!
 
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AOA everyone,
Actually I'm in a really confused state, my problem is related to M1 mechanics and physics....Alright, so we all know that when a simple object like a block of wood moves in a forward direction there is kinetic friction between the block and the floor in the opposite direction.... But things get tricky when it comes to an individual wheel, my mind is actually boggled about *HOW A WHEEL MOVES FORWARD?*. Several pages on Google state that the axle produces two tangential forces on the top and bottom of the wheel and this produces a torque about the axle. Then they state that the friction is opposite to the rotation of the wheel and so it acts in the forward direction causing the wheel to roll forward. But how can friction (forward) ever be greater than the backward force on the wheel produced by the axle. Some articles even mention static friction and rolling friction acting opposite to the direction of motion and all these contradicting statements on the web are confusing me further. Please help me with my query with a detailed and sensible explanation in terms of whatever I stated above. It would be really benign of you. Thanks in advance!
Particle models are sufficent for M1. Just assume that everything behaves like a particle (has mass but no volume).
You'll only need torque if you do M2 or Further Maths.
 
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You cant simply right 3/8 ln(whatever :p)
Differentiate the denominator. You will get 24. So it will be 3/24ln(whatever) And therefor 1/8 ln (whatever) :p
get it?
Nope ... Differentiate what denominator to give 24?? :eek:
Anywayss i did it by taking 1/8 common out of the two partial fractions to give 1/8*ln((3y+1)/(3y+9))
So +c is not zero but 1/8*ln(1/3) and the end answe still is the same :LOL:
 
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Nope ... Differentiate what denominator to give 24?? :eek:
Anywayss i did it by taking 1/8 common out of the two partial fractions to give 1/8*ln((3y+1)/(3y+9))
So +c is not zero but 1/8*ln(1/3) and the end answe still is the same :LOL:
What french? :p So you got the answer or what? :p
Denominator of 8(3y+1) :p Differentiation will give you 24.
 
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