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Simultaneous equation: (x-3y)=9,(2x+3y)=0

Using one of the equations we express either x in the form of y, or y in the form of x. We then put this expression of x/y into the other equation. This allows us to calculate the numerical values of both x ...
KT
Answered by Kerushan T. • Maths tutor
4948 Views

y = 4(x^3) + 7x ... Find dy/dx

This is a simple differentiation question. To start, you need to know the general method of differentiation. This is: if y = Axb then dy/dx = (A*b)x b-1 There are two terms to differentiate in this problem, ...
EE
Answered by Emilio E. • Maths tutor
4087 Views

ABCD is a rhombus on a graph. B(7,10). AC: y=7-4x. Find an equation for DB in the form tx+py+r=0 where t,p&r are integers.

AC and DB must be perpendicular therefore m 1 m 2 = -1. (we can work out the gradient of DB)-4 m 2 = -1 -----> m 2 = 1/4The equation of a line is y-y 1 =m(x-x 1 ) (sub in x, y and gradient values)y - 7 = ...
AL
Answered by Alexander L. • Maths tutor
3342 Views

Given that A(sin θ + cos θ) + B(cos θ − sin θ) ≡ 4 sin θ, find the values of the constants A and B.

Since this must be true for all values of θ, and cos and sin are distinct functions, no non-zero multiple of cosθ could ever be equal to 4 sinθ for all values of θ. Therefore, the overall multiple of cosθ on...
DB
Answered by David B. • Maths tutor
8769 Views

Find the derivative with respect to x, of 5cos(x)+ 4sin(x)

f(x) = 5cos(x) + 4sin(x)to find f , (x) this is just another notation for the derivative.To differentiate trigonometry I always use this one simple trick which I will show on the white board better sin cos -...
RP
Answered by Ryan P. • Maths tutor
4994 Views