Answer:
LHS=cos^4(A/2)-sin^4(A/2)
={cos^2(A/2)}^2 -{sin^2(A/2)}^2
={cos^2(A/2) - sin^2(A/2)}{cos^2(A/2) +sin^2(A/2)}
=cosA×1
=cosA
(3 x 2 = 6 - 2 x +4) + (-8x-3=-24) i think.
The prism has 6 faces.
Each pair of opposite faces is congruent.
The front and back faces are rectangles that measure 10 cm by 5 cm.
The right and left faces are rectangles that measure 5 cm by 3 cm.
The top and bottom faces are rectangles that measure 10 cm by 3 cm.
Now we find the area of each rectangle.
The front and back faces are rectangles that measure 10 cm by 5 cm.
Each face:
A = 10 cm * 5 cm + 50 cm^2
The right and left faces are rectangles that measure 5 cm by 3 cm.
Each face:
A = 5 cm * 3 cm = 15 cm^2
The top and bottom faces are rectangles that measure 10 cm by 3 cm.
Each face:
A = 10 cm * 3 cm = 30 cm^2
There are two faces shaped like each rectangle above, so we multiply each rectangle's area by 2, and we add them together.
total surface area = 2 * 50 cm^2 + 2 * 15 cm^2 + 2 * 30 cm^2
total surface area = 100 cm^2 + 30 cm^2 + 60 cm^2
total surface area = 190 cm^2
