Question

if cos75=x, what is the value in terms of x:
(sin165-cos75)/1+(cos15)(cos165)

Answer 1

\(\bf \cfrac{sin(165^o)-cos(75^o)}{1-cos(15^o)cos(165^o)}\quad ?\)

Answer 2

for the denominator, it is 1+, not 1- :)

so this means you can help me? :D

Answer 3

\(\bf \cfrac{sin(165^o)-cos(75^o)}{1+cos(15^o)cos(165^o)}\) right?

Answer 4

yeap

Answer 5

\( \bf \cfrac{sin(165^o)-cos(75^o)}{1+cos(15^o)cos(165^o)}\implies \cfrac{[sin(90^o+75)]-cos(75^o)}{1+cos(90^o+75^o)cos(90^o+75^o)}\\ \quad \\
\cfrac{[sin(90^o)cos(75^o)+cos(90^o)sin(75^o)]-cos(75^o)}
{
\begin{array}{llll}
1+[cos(90^o)cos(75^o)+sin(90^o)sin(75^o)]\\\ \bf [cos(90^o)cos(75^o)-sin(90^o)sin(75^o)]
\end{array}}\)

Answer 6

anyhow.... I need to dash
keep in mind that \(\bf sin(90^o)=1\qquad cos(90^o)=0\qquad cos(75^o)=x\)

replace accordingly :)

Answer 7

you are blessing on this earth thank you so much!!!!