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solve 2cos^2(x) - cos(x) = 0 on the interval 0<=x < 180

we start y factoring and solving for each equation: cos(x) (2cos(x) - 1) = 0 this means: cos(x) = 0 and cos(x) = 1/2 from the first equation we get: x = 90 and from the second equation using the known trigon...
DS
Answered by Dimitris S. Maths tutor
9451 Views

Expand the brackets and simplify: 7(2x+3y)-x(14-y)

= 14x+21y-14x+xy =y(21+x)
IA
Answered by Ilan A. Maths tutor
6020 Views

Create a program that checks for syntactical errors in an email address.

#Of course this question could be expanded into a program as large or small as desired, dependant on how rigorous wants the program to become. The setup I created here checks for some basic syntactical error...
CH
1986 Views

y = artanh(x/sqrt(1+x^2)) , find dy/dx

Some of these examiners quite like asking students to find the derivative of an inverse trig or hyperbolic function to try and catch someone off guard. The best way to approach these is to first multiply bot...
EL
7922 Views

simplify and rationalise 1/ sqrt(12)

Start by simplifying the denominator - We can write sqrt(12) as sqrt (4*3). - This can be written as sqrt(4) * sqrt(3) - We know the square root of 4 is 2. sqrt(3) is not a integer so we leave that as sqrt(3...
MF
10269 Views