Answer:
The picture that does not contain enough information to prove that ΔABC = ΔDEF is
(3) Picture (3)
Step-by-step explanation:
The given information in picture (3) is the Angle-Side-Side of ΔABC corresponds with the Angle-Side-Side of ΔDEF,
However, the condition of Angle-Side-Side of ΔABC, is not sufficient to prove that ΔABC is congruent to ΔDEF congruency because the length of the unknown side can have two possible values
Equilateral triangles have equal sides
117/3 = 39 mm. All the sides equal to
39 mm
Solution: 39mm
Answer: 14p +70
Step-by-step explanation:
Answer:
We have to prove
sin(α+β)-sin(α-β)=2 cos α sin β
We will take the left hand side to prove it equal to right hand side
So,
=sin(α+β)-sin(α-β) Eqn 1
We will use the following identities:
sin(α+β)=sin α cos β+cos α sin β
and
sin(α-β)=sin α cos β-cos α sin β
Putting the identities in eqn 1
=sin(α+β)-sin(α-β)
=[ sin α cos β+cos α sin β ]-[sin α cos β-cos α sin β ]
=sin α cos β+cos α sin β- sinα cos β+cos α sin β
sinα cosβ will be cancelled.
=cos α sin β+ cos α sin β
=2 cos α sin β
Hence,
sin(α+β)-sin(α-β)=2 cos α sin β
