16. The value of sin² 5° + sin² 10° + sin² 15° + … + sin² 90° is equal to explain in better way ok

11.5

Step-by-step explanation:

Let think mathematically. We have a finite series.

sin² 5° + sin² 10° + sin² 15° + … + sin² 90° . Remeber that sin is a periodic function, and we also know that

and

also that

I'm imying that two angles that add up to 90 will make cancel out to 1.

Our full series will be

Angle measures increasing by 5 so

85+5=1

80+10=1

75+15=1

70+20=1

65+25=1

60+30=1

55+25=1

50+30=1

sin^2(45) is the same as sin(45)sin(45)=1/2.

And sin^2(90)=1 So our value is 9.5

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.

l.jnl.j/n.m,lm,

step-by-step explanation: