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Solve simultaneously: x + y + 3 = 0 and y = 2x^2 +3x - 1

First Step: I believe here it is important to firstly look at each equation on its own and just try to think how the examiner would want you to answer this type of question. Second Step: Recognise that both ...
JS
Answered by Jamie S. Maths tutor
5171 Views

Solve the equation; 4 cos^2 (x) + 7 sin (x) – 7 = 0, giving all answers between 0° and 360°.

4 cos 2 (x) + 7sin (x) – 7 = 0 (1) Using the identity sin 2 (x) + cos 2 (x) = 1, rearrange to give; cos 2 (x) = 1 - sin 2 (x) (2) Sub (2) into (1) ... Giving; 4 ( 1 - sin 2 (x) ) + 7sin (x) - 7 = 0 Expand br...
CS
Answered by Connor S. Maths tutor
19418 Views

Find the factors of x^3−7x−6

To find the factors of x 3 -7x-6, a method called equating coefficients can be used. Firstly, set the equation to zero and find a suitable number which satisfies the equation, in this case x=-1 satisfies the...
MW
Answered by Michael W. Maths tutor
12809 Views

Differentiate a^x with respect to x

y=a^x take natural logs (also written as ln or log base e) of both sides lny=lna^x by logarithms rules lna^x=xlna lny=xlna Now differentiate implicitly 1/y = (dx/dy)lna Note here lna is just a constant, then...
JM
Answered by James M. Maths tutor
43004 Views

How do I do integration by substitution?

There are a number of integrals that we can evaluate directly, called elementary functions:integral[ x dx ] = x 2 /2 + Cintegral[cos( x ) dx ] = sin( x ) + C However, most integrals cannot be solved so direc...
MT
Answered by Matthew T. Maths tutor
6638 Views