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10 The table gives information about the heights of 50 trees. Height (h metres) Frequency 0 < h - 4 ,8, 4 < h - 8 ,21, 8 < h - 12, 12, 12 < h - 16, 7, 16 < h - 20, 2. Work out an estimate for the mean height of the trees.

First find the appropriate mid points of each set of intervals. These will be 2, 6, 10, 14 and 18, and you get these my dividing in two the interval range. Then multiply each midpoint by the corresponding fr...
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Answered by Charlie W. Maths tutor
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Why does the equation x^2+y^2=r^2 form a circle in the Cartesian plane?

The general line equation in the Cartesian plane is given by a x+b y=c, where a, b, and c are given constants. This means that all (x_0, y_0) points that are situated on the line satisfy the equation a x_0+b...
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Answered by Bálint S. Maths tutor
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FP2 (old specification) - How do you find the derivative of arsinhx?

y = arsinhx We can rearrange this to be 2) sinhy = x, which makes this challenge slightly easier as we know that the derivative of sinhx is coshx and vice versa.Knowing the above we get coshy(dy/dx) = 1, we ...
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Answered by Lois M. Maths tutor
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Find the tangent to the curve y = x^2 + 3x + 2 that passes through the point (-1,0), sketch the curve and the tangent.

Differentiate to find dy/dx = 3x + 2;at point (-1,0) dy/dx = -1substitute in to y = mx + c, noting m = -1 and the line passes through (-1,0) yields c = -1y = -x - 1, simple to sketch this line.curve sketchin...
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Answered by Peter W. Maths tutor
3520 Views

How do I find roots of a quadratic equation when I can't factorise?

When factorising isn't working, we can try using the quadratic formula. First, we need our quadratic equation and find a,b and c - the coefficients of x and the constant. Now, we can write out the quadratic ...
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Answered by Freya D. Maths tutor
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