Answer:
a.
b.
Step-by-step explanation:
Dimensions of rectangular piece of cardboard=
According to question
Length of box,l=10-2x
Breadth of box,b=6-2x
Height of box,h=x
a.
Volume of box=
Substitute the values in the formula
Volume of box=

b.Surface area of box=
Because the box has no lid
Substitute the values in the formula
Surface area of box=
Surface area of box=
Surface area of box=
Surface area of box=
Surface area of box, S(x)=
A. 4times y+2 b. 5-x times 3 times y c. -2 times y-3 d. -7 times 4+x e. 16 times x -8 divided by 4 f. 1 divided by 3 times 2 times x +3
sorry I tried to make it out the best that I could I don't have all the symbols so I just wrote out the divide and multiply parts
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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