# Drongoski's latest activity

• Drongoski reacted to hogzillaAnson's post in the thread Trig q with Like.
It's essentially two applications of the double angle formulae. We are in quadrant 4, which means that cosine is + and sine is - (as...
• Drongoski replied to the thread BoS meet up.
Where the place?
• Drongoski reacted to jimmysmith560's post in the thread help plsplspls with Like.
It seems like you might have made a mistake somewhere, since it appears that the correct answer is 3\sqrt{10} according to the following...
• Drongoski replied to the thread Trig q.
Is answer ??: \frac {47}{72} - \sqrt { \frac {\sqrt {119} + 12} {24}}
• Drongoski reacted to Nedom's post in the thread Is MX2 really just practice with Like.
Personally for maths I never believed in doing the amount of papers that people preach so passionately about. Doing a few to get a feel...
• Drongoski reacted to hogzillaAnson's post in the thread Trig with Like.
Using the general solution formula is very efficient, but it's not in the current syllabus, which means it's not on the reference sheet...
• Drongoski replied to the thread Trig.
The general angle formulae for sin x = sin a, cos x = cos a and tan x = tan a are: \\ $sin x =$ sin\theta: x = n\pi +(-1)^n \theta...
• As an aside, do you know that the word "algebra" comes from the Arabic: "al jabr"?
• Drongoski replied to the thread Trig.
sin3x = cos x =sin(\frac{\pi}{2}-x)\\ \\ \therefore 3x = n\pi + (-1)^n (\frac {\pi}{2} - x) (n = 0, 1, 2, . . .) \\ \\ \$For n = 0...
• I think it would be highly impractical to teach 2 students with different texts simultaneously. Is it not possible to tutor each...
• Drongoski replied to the thread Complex vector q.
The diagonals of a kite also intersect at 90 degrees; so should work. MABC here is both a kite(a kite does not normally have all 4 sides...
• Drongoski replied to the thread Complex vector q.
For (ii) let the "centre" of the regular hexagon be M ( M is also the common mid-points of AD, BE & CF). All the triangles MAB, MBC...
• Drongoski replied to the thread Sequences and Series (again).
Q1. S_n = \frac {n}{2}(2a + (n-1)d) \\ \\ \text{ is simply the formula for sum of the 1st n terms of the the A.P.: a, a+d, a+2d...
• Algebra, trigonometry, calculus (derivatives, integrals) are the big ones. Also vectors are important
• Read up on Mechanics (in Physics). Maybe get friend to help you in Mechanics and further Maths. Or, if you can afford it, come to me...