The maximum and minimum of sine function y = - 6sin (2X-4 π) + 1 Seeking process

The maximum and minimum of sine function y = - 6sin (2X-4 π) + 1 Seeking process

Y = - 6sin (2x - π / 4) + 1 because - 1 = - 6,
7> = Y > = - 5 the maximum is 7 and the minimum is - 5