Recent content by williamwong0402

Thank you for your reply. the given has X=11.9m /Y=1.4m / V=170km/h g=-9.81 i don't know how can find y0y or t i didn't, just one picture

Thank you for your reply yes , i made a mistake , it is 170km/h

Homework Statement Serving at a speed of 170 km/h a tennis player hits the ball at a height of 2.5 m and an angle θ below the horizontal. The service line is 11.9 m from the net, which is 0.91 m high. What is the angle θ such that the ball just crosses the net? Will the ball land in the service...

ok ~ thank you so much

thank you ~:smile: The answer: $$ \frac{ x \frac{ 5 }{ 2 } }{ 5 } + \frac{ 2x \frac{ 3 }{ 2 } }{ 3 } + \sqrt{x} $$ Am i right ?

$$ ∫ \frac{ (1-x)^2 }{ 2 \sqrt{x} } dx$$ $$ =∫ \frac{ (x^2+2x+1) }{ 2 \sqrt{x} } dx$$ $$ Let u = \sqrt{x} $$ $$ dx= \frac{ 2du }{ x^{\frac{ -1 }{ 2 }} } $$ $$ ∫\frac{ (x^2+2x+1) }{ 2u } \frac{ 2du }{ x^{\frac{ -1 }{ 2 }} }$$ and then i have no idea what is next step thank you very much

Homework Statement Homework Equations k∫[ƒ(x)]n ƒ'(x) dx The Attempt at a Solution i tried to using algebraic substitution to determine that i had let u = 1-x or X2-2x+1 or x or root(x) but it still cannot solve it. Please give me hint how to solve it. Thank you [/B]

Thank you ~i got it i just thought the other way more complex:wink:

like this? but how can get force of vector by multiplying

Hi everyone please help how can i find the force in Q(a)(ii)?