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Prove that 12 cos(30°) - 2 tan(60°) can be written as √k where k is an integer, state the value of k.

Conversion of trigonometric functions: cos(30°) = √3 / 2 tan(60°) = √3 Computing equation with trigonometric substitutions: 12 cos(30°) - 2 tan(60°) = 12 (√3 / 2) - 2 (√3) = (12 / 2) x √3 - 2√3 = 6√3 - 2√3 =...
ND
Answered by Nic D. • Maths tutor
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How do you know when to use sin, cos and tan?

First draw the triangle and label all the information you have as well as the unknown angle or side length. There should be at least one angle labelled with some informtion - use this angle to label the oppo...
AW
Answered by Anna W. • Maths tutor
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Expand and simplify the expression (x+5)(x+8).

This question is about multiplying two brackets together. There are two parts to each bracket: x , +3 and x , +5 . The parts in the first bracket must each be multiplied by both parts in the second bracket. ...
JC
Answered by Jamie C. • Maths tutor
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What does it mean to "complete the square"?

Completing the square is a useful method of rearranging a quadratic equation so the unknown ("x") only appears in it once. The theory of completing the square tells us that we can take a quadratic ...
CG
Answered by Caitlin G. • Maths tutor
4809 Views

Consider a right-angled triangle with an inside angle of 30° and a hypotenuse of 8cm. Calculate the length of the opposite side to the 30° angle.

Recall the trigonometry rule SOH/CAH/TOA (Silly Old Hitler Couldn't Advance His Troops Over Africa). Label: Draw the triangle and label the sides with Hyp, Opp & Adj. Choose: Pick which equation to use f...
JL
Answered by Joshua L. • Maths tutor
4937 Views