Question 1020959
Hi there,
Cos(a-b)/sina*sinb=cota*cotb+1
cosacosb + sinasinb/sina*sinb
= cosacosb/sinasinb = cotacotb
As cos/sin = cot
And
+ sinasinb/sinasinb = 1
So, Cos(a-b)/sina*sinb=cota*cotb+1
Hope this helps :-)