1
AP EAPCET 2025 - 21st May Evening Shift
MCQ (Single Correct Answer)
+1
-0

$$ \cos ^3 \frac{\pi}{8} \cos \frac{3 \pi}{8}+\sin ^3 \frac{\pi}{8} \sin \frac{3 \pi}{8}= $$

A

$\frac{1}{2 \sqrt{2}}$

B

$\frac{1}{2}$

C

$\frac{1}{\sqrt{2}}$

D

$\frac{1}{4}$

2
AP EAPCET 2025 - 21st May Evening Shift
MCQ (Single Correct Answer)
+1
-0

If $A+B+C=\frac{\pi}{4}$, then $\sin 4 A+\sin 4 B+\sin 4 C=$

A

$4 \cos 2 A \cos 2 B \cos 2 C$

B

$4 \sin 2 A \sin 2 B \sin 2 C$

C

$1+4 \sin 2 A \sin 2 B \sin 2 C$

D

$1+4 \cos 2 A \cos 2 B \cos 2 C$

3
AP EAPCET 2025 - 21st May Evening Shift
MCQ (Single Correct Answer)
+1
-0

Number of solutions of the equation $\cos \theta+\cos 2 \theta-\sqrt{3}(\sin \theta+\sin 2 \theta)+1=0$ lying in the interval $(0,2 \pi)$ is

A

3

B

6

C

5

D

4

4
AP EAPCET 2025 - 21st May Evening Shift
MCQ (Single Correct Answer)
+1
-0

If $x$ is a real number, then the number of solutions of $\tan ^{-1}(\sqrt{x(x+1)})+\sin ^{-1}\left(\sqrt{x^2+x+1}\right)=\frac{\pi}{2}$ is

A

1

B

2

C

3

D

4