A = (sin²α -1)/(1-cos²α) = -(1-sin²α)/(1-cos²α) = -cos²α/sin²α = - ctq²α
при α= π/4 получаем
A = - ctq²π/4 = -1.
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<span>(sin^2 a-1)/1-cos^2 a ) !!!</span>
F=1.8C+32=1.8*67+32=152.6 F -------------------------------------
1) (х+2)^2-(х+8)^2=х^2+2x+4-x^2-8x-64=-6x-60
-6x-60
-6x=60
x=-10
2) x^3-9x
x(x^2-9)\
x=0
x^2-9=0
x^2=9
x=+3;-3
3) (x^6)8/(X^3*x^7)4
X^48/(x^10)4
x^48/x^40=x^8
5) (10-2)^2+20=(9+x)(10+x)
100-10x+x^2+20=90+9x+10x+x^2
100-90+20=29x
30=29x
x=30/29