Question

find the least value of 4(cosec)2@+9(sin)2@

step by step please

here 2 is square

Answer 1

1. This is totally in the wrong section dude :-D You posted this in Geography
2. Did you mean this? \(4 \csc^2\theta + 9 \sin^2\theta \)
3. Step-by-step:

\(\large\frac{d}{d\theta }(4 \csc^2\theta + 9 \sin^2\theta )\)
\(9\large (\frac{d}{d\theta }(\sin^2\theta ))+4 (\frac{d}{d\theta }(\csc^2\theta ))\)
\(9\large (\frac{d}{d\theta }(\sin^2\theta ))+4 (2 \csc\theta (\frac{d}{d\theta }(\csc\theta )))\)
\(9\large (2 \sin\theta (\frac{d}{d\theta }(\sin\theta )))+8 \csc(x) (\frac{d}{d\theta }(\csc\theta ))\)
\(\large18 \sin\theta (\frac{d}{d\theta }(\sin\theta ))+8 \csc\theta (-\cot\theta \csc\theta )\)
\(\large18 \sin\theta \cos\theta -8 \cot\theta \csc^2\theta \)

Questions?