Since these are right triangles you can use the pythagorean theorem
a² + b² = c²
a = one leg of the triangle
b = the other leg of the triangle
c = the hypotenuse
1. 4² + 3² = c²
16 + 9 = c²
25 = c²
√25 = √c²
5 = c
c = 5cm
2. 5² + 12² = c²
25 + 144 = c²
169 = c²
√169 = √c²
13 = c
c = 13in
4. 7² + 9² = c²
49 + 81 = c²
130 = c²
√130 = √c²
11.4 = c
c = 11.4cm
5. a² + 10² = 15²
a² + 100 = 225
a² = 125
√a² = √125
a = 11.2ft
2cos2x=y
dy/dx(2cos2x)=-4sin2x
d/du cosu= u'×cos'u=-u'×sinu
d/du sinu= u'×sin'u= u'×cosu
d/du tanu = u'×(1+tan²u)
d/du cotu = u'×-(1+cot²u)
proof for cosu :
cos2x= 1-2sin²x
or 2cosx²-1
or cos²x-sin²x
we will one of this fro example let's take the first one
d/dx 1-2sin²x=0-2×2(sinx)×cosx=-2sin2x
and we have 2 in the begining so its -4sin2x
Answer:
Step-by-step explanation:
X^2-10x-8=0
Solve simultaneously
6+5+11+15=37
so she sold 37 cups of lemonade in 4 hours
