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3/5 of a number is 162. what is the number?

SOLVING ALGEBRAICALLY3/5 of "a number" = 3/5 of "x"3/5 of x is equivalent to (3x)/5(3x)/5 = 162Move the "5" to the other side by multiplying:3x = (162x5) = 810We now have 3x ...

Answered by Fred J. • Maths tutor

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Show that tan(x) + cot(x) = 2cosec(2x)

For this we have to use trignometric identities, e.g Tan(x)= sin(x)/cos(x), sin²(x) + cos²(x) = 1, 1/sin(x) = cosec(x)
ta...

Answered by Moin B. • Maths tutor

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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 correspondin...

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 ax+by=c, where a, b, and c are given constants. This means that all (x_0, y_0) points that are situated on the line s...

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)...

Answered by Lois M. • Maths tutor

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