Evaluate 3/5r +5/8swhen r =14 and s =8

Step-by-step explanation:

14×5=70

8×8=64

(3/70) + (5/64)

= (3×64)+(5×70)

‐

70×64

= (192+350)/448

=542/448

= 271/224

Step-by-step explanation:

cos(90) = 0

around this point the cos function "mirrors" with opposite signs. cos(<90) is positive and cos(>90) is negative.

but |cos(90-a)| = |cos(90+a)| for 0 <= a <= 90

75 = 90 - 15

105 = 90 + 15

so, a = 15

and because of

|cos(90-a)| = |cos(90+a)| for 0 <= a <= 90

cos (90-15) = cos(75) = -cos(90+15) = -cos(105)