If sin 18° = 0.3090,cos 18° = 0.9511, sin 22° = 0.3746, and
cos 22° = 0.9272, then what is sin 40°?

0.6428

Step-by-step explanation:

Using the addition formula for sine

sin(x + y) = sinxcosy + cosxsiny

Hence

sin40 = sin(18 + 22)

= sin18cos22 + cos18sin22

= (0.3090 × 0.9272) + (0.9511 × 0.3746)

= 0.2865 + 0.3563

= 0.6428

1) c 2143.6 cm

2) c 113.0 m

3) a 33.5 ft

4)   d 2 cm

5) c 20 mm

6) 180 in

7) d 120 ft

see explanation

step-by-step explanation:

since the sequence is geometric there is a common ratio r between consecutive terms, that is

r = 4 ÷ - 2 = - 2

r = - 8 ÷ 4 = - 2

r = 16 ÷ 8 = - 2

the next term - 13 must be incorrect as it should be - 32 for the sequence to be geometric.

the first 4 terms are therefore geometric with common ratio r = - 2