Help with question please (1 Viewer)

[dabatman]

Hi,

Can anyone please find the exact value of this question please?

 

[Squar3root]

lhs = sin(x+30) + cos(x+30)

now cos(x) = sin (90-x)

so we get

sin(x+30) + sin(90 - (x+30))

= sin(x+30) + sin (60-x)

using sum to product we get

2sin( [x+30 +60+x ]/2) * cos ([x + 30 - (60 -x)]/2

= 2 sin(90/2) cos([2x-30]/2)

= sqrt(2)cos(x-15)

 

[Squar3root]

using the identity


using product to sums







first time using latex in long time no h8 pls