Answer:
first one
Step-by-step explanation:
hhhhjnbbbnhhh
Let’s first cut/separate this figure into two shapes: rectangle and a triangle
The area of the rectangle: 9 • 2 = 18
The area of the triangle: 1/2 • 8 • 4 = 16
The total area: 18 + 16 = 34
He needs 34 m square of grass
Answer:
hdvbn
Step-by-step explanation:
nfshvjjnmmnjjmbm
Double-angle formulas:
2sinФcosФ=sin(2Ф) /:2
sinФcosФ=1/2*sin(2Ф)
sin(Ф/6)cos(Ф/6)=1/2*sin(2*Ф/6)=1/2*sin(Ф/3)
cos²Ф-sin²Ф=cos(2Ф)/*7
7cos²Ф-7sin²Ф=7cos(2Ф)
7cos²(Ф/9)-7sin²(Ф/9)=7cos(2*Ф/9)=7cos(2Ф/9)