• A. $\sin \theta =1+{\cos }^2\theta$
• B. ${\sin }^2\theta =1-{\cos }^2\theta$
• C. ${\sin }^2\theta -{\cos }^2\theta =1$
• D. $\sin \theta =\frac{1}{\cos \theta }$

Answer: Option B

Explanation:

• A. $\left(x+a+2\right)\left(x-a+1\right)$
• B. $\left(x+a-2\right)\left(x+a+1\right)$
• C. $\left(x+a+2\right)\left(x-a-1\right)$
• D. $\left(x+a+2\right)\left(x-a-1\right)$

Answer: Option C

Explanation:

• A. $-2$
• B. $2$
• C. $4$
• D. $14$

Answer: Option A

Explanation:

• A. $3$
• B. $9$
• C. $-3$
• D. $-9$

Answer: Option C

Explanation:

• A. $\frac{৩}{৪}$
• B. $\frac{২}{৫}$
• C. $\frac{১}{৬}$
• D. $\frac{৫}{৮}$

Answer: Option A

Explanation:

• A. $a{x}^2+bx+c=0$
• B. $y^2=ax$
• C. $3x^2+3y^2=15$
• D. $y^2=4x+4$

Answer: Option C

Explanation:

• A. $\frac{a+b}{a^2}$
• B. $\frac{a}{b}$
• C. $1$
• D. $\frac{a-b}{a^2}$

Answer: Option C

Explanation:

• A. ${\mathrm{\pi r}}^2$
• B. ${\mathrm{\pi r}}^2/2$
• C. $4{\mathrm{\pi r}}^2$
• D. কোনটিই নয়

Answer: Option D

Explanation:

• A. ${\mathrm{\pi r}}^2$
• B. $2{\mathrm{r}}^2\mathrm{\pi }$
• C. $2\mathrm{\pi r}$
• D. কোনোটিই নয়

Answer: Option A

Explanation:

• A. $\frac{n\left(n+1\right)}{2}$
• B. $\frac{n^2{\left(n+1\right)}^2}{4}$
• C. $n^2$
• D. $\frac{n\left(n+1\right)\left(n+2\right)}{6}$

Answer: Option A

Explanation:

• A. ${\sec }^2\theta =1+{\tan }^2\theta$
• B. ${\sec }^2=1-{\tan }^2\theta$
• C. $\tan \theta =\frac{\cos \theta }{\sin \theta }$
• D. ${\sin }^2\theta -{\cos }^2\theta =1$

Answer: Option A

Explanation:

• A. $9$
• B. $10$
• C. $12$
• D. কোনোটিই নয়

Answer: Option B

Explanation:

• A. $\frac{3}{5}$
• B. $\frac{5}{3}$
• C. $\frac{4}{3}$
• D. $\frac{5}{4}$

Answer: Option B

Explanation:

• A. $a^6-1$
• B. $\left(a-a\right)\left(a^3+1\right)$
• C. $\left(a^4+1\right)\left(a-1\right)$
• D. $a^6+1$

Answer: Option A

Explanation:

• A. $1400x$ টি
• B. $\frac{1400}{100+x}$ টি
• C. $\frac{100+x}{1400}$ টি
• D. $\frac{1400+x}{100}$ টি

Answer: Option B

Explanation: