Q.
Match the following :
List I
List II
P
Exact value of $\cos 40^{\circ}\left(1-2 \sin 10^{\circ}\right)=$
1
$\frac{1}{4}$
Q
Value of $\lambda$ for which lines are concurrent $x+y+1=0,3 x+2 \lambda y+4=0$, $x+y-3 \lambda=0$ can be
2
$\frac{1}{2}$
R
Points ( $k, 2-2 k),(-k+1,2 k)$ and $(-4-k, 6-2 k)$ are collinear then sum of all possible real values of ' $k$ ' is
3
$\frac{3}{2}$
S
Value of $\displaystyle\sum_{k=3}^{\infty} \sin ^k\left(\frac{\pi}{6}\right)=$
4
$-\frac{1}{2}$
| List I | List II | ||
|---|---|---|---|
| P | Exact value of $\cos 40^{\circ}\left(1-2 \sin 10^{\circ}\right)=$ | 1 | $\frac{1}{4}$ |
| Q | Value of $\lambda$ for which lines are concurrent $x+y+1=0,3 x+2 \lambda y+4=0$, $x+y-3 \lambda=0$ can be | 2 | $\frac{1}{2}$ |
| R | Points ( $k, 2-2 k),(-k+1,2 k)$ and $(-4-k, 6-2 k)$ are collinear then sum of all possible real values of ' $k$ ' is | 3 | $\frac{3}{2}$ |
| S | Value of $\displaystyle\sum_{k=3}^{\infty} \sin ^k\left(\frac{\pi}{6}\right)=$ | 4 | $-\frac{1}{2}$ |
Trigonometric Functions
Solution: