Question

Regarding the R formula..

How do you find θ given this:
5sinθ + 2cosθ

Answer 1

does that equal something ?

Answer 2

nope

well, they asked to find θ for a maximum length

Answer 3

so basically say length AB

AB = 5sinθ + 2cosθ

Answer 4

R formula? 0_o

Answer 5

We want to find the angle \(\Large\rm \theta\) which maximizes the length of the curve \(\Large\rm AB\) ?

Answer 6

AB is a straight line

Rformula
like asinθ±bcosθ=Rsin(θ∓α)

Answer 7

Okay maybe the question itself would shed more light



Given that <QOB is a variable angle θ, where 0˚< θ < 90˚, obtain an expression for AB in terms of θ.
this i already found, which is AB = 5sinθ + 2cosθ

Then express AB in the form of Rsin(θ+α),
which is
(√25+4)sin(θ+basic angle)
=(√29)sin taninverse(2/5)
—this is as much as i could simplify??—

hence find the value of θ for which AB has a maximum length.