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Imagine a sector of a circle called AOB. With center O and radius rcm. The angle AOB is R in radians. The area of the sector is 11cm². Given the perimeter of the sector is 4 time the length of the arc AB. Find r.

11 = 1/2 r²RAB = x = rRr + r + x = 4x2r = 3rRR = 2/3r²R = 22r² = 33r = √33

Answered by Alice S. • Maths tutor

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x^3 + 3x^2 + 2x + 12

3x² + 6x + 2

Answered by Jiawang Q. • Maths tutor

3577 Views

How to perform integration by substitution. (e.g. Find the integral of (2x)/((4+(3(x^2)))^2)) (10 marks)

We begin by looking at the integral by itself. The first thing we must do is evaluate what type of integration we should perform. It's always important to make sure that it's not a standard integral such ...

Answered by Kenneth B. • Maths tutor

4038 Views

Calculate the mean and standard deviation from the following data

Time (Minutes) to complete an exam: 40, 38, 67, 84, 92, 43, 58, 57, 48, 50, 50, 74, 86Mean: (add up the scores = 787; then divide by the number of participants = 13)

Answered by Annabelle K. • Psychology tutor

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What is DNA?

DNA carries the genetic information that codes for instructions in our body and other organisms. DNA is deoxyribonucleic acid. It is found in the shape of a double helix. The conclusion that DNA is in the...

Answered by Vicky B. • Biology tutor

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