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solve 3 cos (2y )- 5 cos( y)+ 2 =0 where 0<y<360 degrees

cos(2y)= (cos(y))^2 - (sin(y))^2 identitynow consider identity (cos(y))^2+(sin(y))^2=1by rearranging this to (cos(y))^2 - 1 = - (sin(y))^2 we can now substitute it into our first identity to obtaincos(2y)= 2...
LS
Answered by Leah S. • Maths tutor
4078 Views

Solve the Equation: 2ln(x)−ln (7x)=1

This is an equation laid out in terms of the natural logarithm, which essentially is the reverse function of e x . From this equation we need to find a solution for x =? Since we know that this equation invo...
DG
Answered by Dhruv G. • Maths tutor
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How do I differentiate an algebraic expression? (e.g. y=3x^4 - 8x^3 - 3) [the ^ represents x being raised to a power]

y=3x 4 -8x 3 -3 Let's say we want to calculate dy/dx. For a term A x n , the differential with respect to x is An x n-1 . For a constant value, we can say that n=0 because x 0 =1. This means that when you di...
PC
Answered by Patrick C. • Maths tutor
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Find the coordinates of the stationary points of the curve 3x=y+6x+3

First, straight away from reading the question you know this question will involve differentiating the function with respect to x so immediately you want to re-write the equation in terms of y which in this ...
JS
Answered by James S. • Maths tutor
4519 Views

If y = ln (x+1) sin x , find dy/dx

u = ln (x+1) v = sin x du/dx = 1/(x+1) dv/dx = cos x Therefore, by the product rule, dy/dx = [sin x / x+1] + [ln (x+1) cos x]
EC
Answered by Edward C. • Maths tutor
7195 Views