Question
Evaluate the following:
If $\sin(\text{A}+\text{B})=1$ and $\cos(\text{A}-\text{B})=1,0^\circ\leq(\text{A}+\text{B})\leq90^\circ$ and $\text{A}>\text{B}$ then find A and B.

Answer

Here, $\sin(\text{A}+\text{B})=1$
$\Rightarrow\sin(\text{A}+\text{B})=\sin90^\circ$ $[\because\ \sin90^\circ=1]$
$\Rightarrow\text{A}+\text{B}=90^\circ\dots(\text{i})$
Also, $\cos(\text{A}-\text{B})=1$
$\Rightarrow\cos(\text{A}-\text{B})=\cos0^\circ$ $[\because\ \cos0^\circ=1]$
$\Rightarrow\text{A}-\text{B}=0^\circ\dots(\text{ii})$
Solving (i) and (ii), we get:
A = 45° and B = 45°.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

A survey regarding the height (in cm) of 51 girls of class X of a school was conducted and the following data was obtained.
Hight in cm
Number of girls
Less than 140
4
Less than 145
11
Less than 150
29
Less than 155
40
Less than 160
46
Less than 165
51
Find the median height.
In a rectangle, if the length is increased by 3 meters and breadth is decreased by 4 meters, the area of the rectangle is reduced by 67 square meters. If length is reduced by 1 meter and breadth is increased by 4 meters, the area is increased by 89 Sq. meters. Find the dimensions of the rectangle.
In garden, there are some rows and columns. The number of trees in a row is greater than that in each column by 10. Find the number of trees in each row if the total number of trees are 200.
A businessman bought some items for ₹ 600. Keeping 10 items for himself he sold the remaining items at a profit of ₹ 5 per item. From the amount received in this deal he could buy 15 more items. Find the original price of each item.
If the equation $\left(1+m^2\right) x^2+2 m c x+\left(c^2-a^2\right)=0$ has equal roots, prove that $c^2=a^2\left(1+m^2\right)$.
A wholesaler purchased electric goods for the taxable amount of Rs. 1,50,000. He sold it to the retailer for the taxable amount of Rs. 1,80,000. Retailer sold it to the customer for the taxable amount of Rs. 2,20,000. Rate of GST is 18%. Show the computation of GST in tax invoices of sales. Also find the payable CGST and payable SGST for wholesaler and retailer.
A two-digit number is 4 times the sum of its digits. If 18 is added to the number, the digits are reversed. Find the number.
Ajay sharma repays the borrowed amount of ₹ 3,25,000 by paying ₹ 30500 in the first month and then decreases the payment by ₹ 1500 every month. How long will it take to clear his amount?
Find the possible pairs of coordinates of the fourth vertex D of the parallelogram,if three of its vertices are A(5,6), B(1,-2)and C(3,-2).
Two different dice are rolled simultanceously. Find the probability that the sum of the numbers on the two dice is 10.