Evaluatetan15°
To evaluate:tan15°
We can write 15°=45°-30°
Taking tanget on both the sides, we get
tan15° =tan(450-300)
Applying formula tan(A-B)=tanB-tanB1+tanAtanB, we get
tan15° =tan450-tan3001+tan450tan300
= 1-1√31+1×1√3 (From trigonometric angle table tan450=1and tan300=13)
=√3-1√31+1√3
= (√3-1)√3(√3+1)√3
=(√3-1)√3×√3(√3+1)
=√3-1√3+1
Thus, the required value of tan15°=√3-1√3+1.
Evaluate: 15C8+15C9−15C6−15C7
Evaluate 15+(-8)