\(\left(r \cdot {\left(\frac{\sin b}{{\left(\cos a \cdot \cos b\right)}^2 - {\left(\sin a \cdot \sin b\right)}^2}\right)}^{1}\right) \cdot {\left(\cos a \cdot \cos b + \sin a \cdot \sin b\right)}^{1}\)
- Started with
\[r \cdot \frac{\sin b}{\cos \left(a + b\right)}\]
7.8
- Using strategy
rm 7.8
- Applied cos-sum to get
\[r \cdot \frac{\sin b}{\color{red}{\cos \left(a + b\right)}} \leadsto r \cdot \frac{\sin b}{\color{blue}{\cos a \cdot \cos b - \sin a \cdot \sin b}}\]
0.2
- Using strategy
rm 0.2
- Applied pow1 to get
\[r \cdot \color{red}{\frac{\sin b}{\cos a \cdot \cos b - \sin a \cdot \sin b}} \leadsto r \cdot \color{blue}{{\left(\frac{\sin b}{\cos a \cdot \cos b - \sin a \cdot \sin b}\right)}^{1}}\]
0.3
- Using strategy
rm 0.3
- Applied flip-- to get
\[r \cdot {\left(\frac{\sin b}{\color{red}{\cos a \cdot \cos b - \sin a \cdot \sin b}}\right)}^{1} \leadsto r \cdot {\left(\frac{\sin b}{\color{blue}{\frac{{\left(\cos a \cdot \cos b\right)}^2 - {\left(\sin a \cdot \sin b\right)}^2}{\cos a \cdot \cos b + \sin a \cdot \sin b}}}\right)}^{1}\]
0.3
- Applied associate-/r/ to get
\[r \cdot {\color{red}{\left(\frac{\sin b}{\frac{{\left(\cos a \cdot \cos b\right)}^2 - {\left(\sin a \cdot \sin b\right)}^2}{\cos a \cdot \cos b + \sin a \cdot \sin b}}\right)}}^{1} \leadsto r \cdot {\color{blue}{\left(\frac{\sin b}{{\left(\cos a \cdot \cos b\right)}^2 - {\left(\sin a \cdot \sin b\right)}^2} \cdot \left(\cos a \cdot \cos b + \sin a \cdot \sin b\right)\right)}}^{1}\]
0.3
- Applied unpow-prod-down to get
\[r \cdot \color{red}{{\left(\frac{\sin b}{{\left(\cos a \cdot \cos b\right)}^2 - {\left(\sin a \cdot \sin b\right)}^2} \cdot \left(\cos a \cdot \cos b + \sin a \cdot \sin b\right)\right)}^{1}} \leadsto r \cdot \color{blue}{\left({\left(\frac{\sin b}{{\left(\cos a \cdot \cos b\right)}^2 - {\left(\sin a \cdot \sin b\right)}^2}\right)}^{1} \cdot {\left(\cos a \cdot \cos b + \sin a \cdot \sin b\right)}^{1}\right)}\]
0.3
- Applied associate-*r* to get
\[\color{red}{r \cdot \left({\left(\frac{\sin b}{{\left(\cos a \cdot \cos b\right)}^2 - {\left(\sin a \cdot \sin b\right)}^2}\right)}^{1} \cdot {\left(\cos a \cdot \cos b + \sin a \cdot \sin b\right)}^{1}\right)} \leadsto \color{blue}{\left(r \cdot {\left(\frac{\sin b}{{\left(\cos a \cdot \cos b\right)}^2 - {\left(\sin a \cdot \sin b\right)}^2}\right)}^{1}\right) \cdot {\left(\cos a \cdot \cos b + \sin a \cdot \sin b\right)}^{1}}\]
0.3