Trigonometry
Which of the following statements correctly describes the procedure for obtaining the graph of y = 8 + 2 cos (x + π/7) from the graph of y = cos x?
Translate the graph of y = cos x by π/7 unit to the right, stretch it vertically by a factor of 2, and translate it by 8 units downward.
Translate the graph of y = cos x by π/7 unit to the left and stretch it vertically by a factor of 8.
Translate the graph of y = cos x by π/7 unit to the right, compress it vertically by a factor of 2, and translate it by 8 units upward.
Translate the graph of y = cos x by π/7 unit to the left, stretch it vertically by a factor of 2, and translate it by 8 units upward.