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When the polynomial 3x^3 +ax+ b is divided by x−2 , the remainder is 2, and when divided by x +1 , it is 5. Find the value of a and the value of b.

Insert the negative values of the divisors and put them into the polynomial. x-2 -> P(2) = 34+2a+b=2 x+1 -> P(-1)=3(-1)+(-1)a+b=5. 22+2a+b=0 -8-a+b=0, then solve the simultaneous equa...

Answered by Egidijus S. • Maths tutor

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How is frequency density calculated?

Frequency divided by class width

Answered by Umamah Y. • Maths tutor

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y is proportional to x^2. When y is 75, x is 5. Find a formula for y in terms of x

y is proportional to x² so this means y = A*x² for some constant A.

When y = 75, x = 5. Put these values in the formula above to find A:

75 = A*25

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Answered by Thomas M. • Maths tutor

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Differentiate 4x^2 + 2ln3x + e^x

To differentiate x² you bring the power of x down, then reduce the power of x by 1, so d/dx(x²) = 2x¹

ln3x differentiates to (d/dx(3x))/3x = 3/3x = 1/x

Answered by Thomas M. • Maths tutor

7965 Views

Differentiate x^2+4x+9.

To differentiate you must look at each term separately. So for x^2 to differentiate we bring the two down to multiply in front of the x and then take one away from the power leaving 2x. For 4x, x is to...

Answered by Iman W. • Maths tutor

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