Question #5baa9

1 Answer
Feb 10, 2017

Given
#y=f(x)=2sin(x-pi/4)#

To get x-intercepts we can put y=0 and solve for #x in [0,4pi]#

So #2sin(x-pi/4)=0#

#=>x-pi/4=npi" where " n in ZZ#

#=>x=npi+pi/4" where " n in ZZ#

Putting #n=0# we get

#x=pi/4#

Putting #n=1# we get

#x=(5pi)/4#

Putting #n=2# we get

#x=(9pi)/4#

Putting #n=3# we get

#x=(13pi)/4#

(a) So points of x-intercepts over #[0,4pi]# are

#(pi/4,0);((5pi)/4,0);((9pi)/4,0);((13pi)/4,0)#

b) For maximum value of y the value of #sin(x-pi/4)=1#

So #x-pi/4=pi/2#
#=>x= pi/4+pi/2=(3pi)/4#

For #x=(3pi)/4" " y=2#

The point(in (0,2pi) where the graph of this function reaches
maximum is #((3pi)/4,2)#

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