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How do you use transformation to graph the sin function and determine the amplitude and period of #y=-2sinx#?

Answer 1

The period is #2pi# and the amplitude is #+-2#

The amplitude of #sin(x)# is #+-1# so #2sin(x)#increases that to #+-2#
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If #y_1=sin(x)" " #then#" "y_2=2y_1=2sin(x)#
So #y_2# is twice as big as #y_1#
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Then by changing #2sin(x)# to #-2sin(x)# what was positive will be negative and what was negative will be positive.

The period does not change. What changes the period is something like #sin(ax)# where #a# is a constant.

The period is #2pi# and the amplitude is #+-2#

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