
Step-by-step explanation:
....

First, solve the parentheses:

Next, the exponential terms

Solve the multiplication:

Add and subtract:
Answer:
( √15 + 8)/7
Step-by-step explanation:
TanA = -√15
.we are to find tan(A-π/4).
In trigonometry
Tan(A-B) = TanA - TanB/1+ tanAtanB
Hence:
tan(A-π/4) = TanA - Tanπ/4/1+ tanAtanπ/4
Substitute tan A value into the formula
tan(A-π/4) = -√15-tanπ/4 / 1+(-√15)(tanπ/4
tan(A-π/4) = -√15-1/1-√15
Rationalize
-√15-1/1-√15 × 1+√15/1+√15
= -√15-√225-1-√15/(1-√225)
= -2√15-15-1/1-15
= -2√15 -16/(-14)
= -2(√15+8)/-14
= √15 + 8/7
Hence the required value is ( √15 + 8)/7
Let us draw a triangle ABC with A=15° ,B=113° and b=7.
Please see the attached image.
We know that the sum of interior angles of a triangle is 180 degrees. Thus, we have

Apply Sine rule in the triangle ABC, we get

Therefore, we have
