Answer:
10.7 grams
Step-by-step explanation:
hey there, again!
this is a similar process the mass is denisty*area HOWEVER keep in mind it's flat so the area is just x deltax while denisity is 3 + sin(x)
mass of rod = integral 0 to 3pi/4 of (3 + sin(x))*x deltax
= integral 0 to 3pi/4 of 3x + xsin(x) deltax
= 0 to 3pi/4 [3/2*x^2 + x(-cos(x)) + sin(x)]
= 10.7 grams