5. (b)
1 + 2 + 22 + 23 +... + 2
LHS !
=
-
1 +
1
2)
ciso + Sis20 + Cis30 +
-
.
-
cisnO
+
+ cost + isino + COS2P + isin20 +
+ 100 +
COS20 + 20330 +.
+
-
+ cosnot Isin no
---
cosno) + 2 (Sino + Sin 20 + Sin 30
Singl
+. - - +
-
Real part
RHS
:
C
This factorisation
step is
·
=
=
=>
crucial in this
this
fine
problem
+ isin
simplifying things.
Since
2- zisinn
sinzos
(e) (
cost .
+
sin
Sin(0)
Real part
~
I + 20s0 + 2020 +.
-
+ cosno
Without
step you'll spend a lot of
2
(os
.
0) Sin (10)
=
·
Sin
02