Friday, May 8, 2009
lol. ps. exam fever nvr update. lol. exams are finally over!!! yay!!! hahaha. except tues gt math but oh well... anws. most interesting thing for the exam week? Me physics paper!!! mwahahaha. I COMPLETED THE WHOLE PAPER WITHOUT CALCULATOR AND HAD 10 MIN EXTRA!!! hahahaha. yalol. at the start i was like. pressing on button like some mad guy then keep slamming the calc against the table until zhw tot i was mad. (she was the invigilator XD). lol. so. i did division of stuff and multiplication the long way. addition and subtraction was mental. (mental calc) actually hor. division easier leh. cause like. if u have like 0.85/1.30, u can convert into fraction and cancel cancel cancel XD. become 85/100 * 130/100. lol. then next question. how to do sine?
like sin 75? haha. ANSWER: DRAW TRIANGLES XD. so. u just draw this triangle with one angle 75 degree. must be right angle hor. then right. sine = o/h right. so u measure the length of the line opp ur angle and divide with the hyp. that is sin75. haha. the size doesnt matter cause u wan the angle and sine is the ratio in the 1st place. XDXD.
question 2. wad abt arcsine? (sine inverse)
even easier lawl. like say u gt arcsin 0.54 (arcsin can only between -1 and 1) ok. so u gt arcsin 0.54. now wad. look ar. wad is arcsin 0.57? its actually the angle that the triangle forms when the triangle has an opp side 57 units and hyp side 100 units. (0.57 = 57/100 = o/h). so how? how to draw 57 cm? but sine is ratio wad. as said. so just divide by 10 lor. ur ruler not that short right? (i used a set square XD). so u have this right angle triangle with a opp of 5.7cm and a hyp of 10cm. then u measure ur teether angle la. which is the one opp ur opp side. haha.
kk. xia ke le.
I walked alone at
4:28 PM